EP0805899B1

EP0805899B1 - Rail element, in particular for subway, tramway and railway tracks

Info

Publication number: EP0805899B1
Application number: EP96901750A
Authority: EP
Inventors: Claudio Favaron; Tiziano Mason
Original assignee: MECNO RAIL Srl; Mecno-Rail Srl
Current assignee: Mecno-Rail Srl
Priority date: 1995-01-26
Filing date: 1996-01-22
Publication date: 1999-11-03
Anticipated expiration: 2016-01-22
Also published as: AU4620496A; DE69605022T2; DE69605022D1; WO1996023106A1; EP0805899A1; ATE186346T1

Abstract

A rail element in particular for subway, tramway and railway tracks, characterised by consisting of a monolithic box structure (2) upperly comprising a seat (10) for removably connecting the wheel guide element (12, 12', 14, 38).

Description

This invention relates to a rail element, in particular for subway, tramway and railway tracks.

The traditional railway or tramway superstructure generally comprises two rails supported by sleepers resting on ballast. In other cases it is also known to replace the sleepers and ballast with a single concrete bed.

If the superstructure is of tramway type, the rails are grooved, and the entire superstructure is embedded in the roadway, with the rail iron surface at the same level as the road surface, and the connection between adjacent rails being made by joints or welding.

However, this type of superstructure and its connection system have certain drawbacks, and in particular:

the need to form a seat of about 70-80 cm depth, with a consequent increase in the unit constructional cost of the line. Even for a superstructure with a concrete bed it is still necessary to excavate a seat of about 50-60 cm depth;
mutual sliding of the surfaces if the connection between adjacent rails is made by joint, with consequent jolting of the vehicle wheel when it passes over;
if the connection is made by welding, the formation of slight depressions due to shrinkage deriving from the different material structure;
noise and vibration problems as these rails generally deform with time, with wear both of the head and of the inner and outer walls.

To obviate this latter problem, which causes considerable annoyance both to the inhabitants of zones surrounding the rail area, and to the occupants of the vehicle using them, it is necessary to provide for frequent maintenance on the installed rail, and in certain cases its total replacement.

Total rail replacement involves on the one hand the problem of cost deriving from the material and the labour employed, and on the other hand problems of service interruption along the line, traffic problems and problems related to the excavation and renovation of the seat housing the rail.

In contrast, if maintenance is carried out on the installed rail there is a certain difficulty in carrying out wear compensation welding on the inner and outer walls and on the rolling surface as this operation is influenced by environmental conditions, and the difficulty of preheating the rail with the risk of detachment of the added material and rail cracking. This operation also causes further discomfort because of the dust and noise which it produces.

Additionally, there is a further problem of a bureaucratic nature which the maintenance concern has to confront, relating to the numerous permits to be obtained for interrupting the road service, for transporting large loads, etc.

It should be noted that these same problems are also encountered for the switch, formed from a movable element known as the switch tongue which is interposed between two fixed elements known as stock rails, each consisting of a piece of rail which is suitably machined in the region below the head, is screwed to a support plate and is welded at its ends to the prolongations of the track rails. The blade, also consisting of a shaped rail element, is thinned at one end to be able to perfectly fit below the head of the adjacent stock rail.

DE-C 9443 discloses a discontinuous framework for connecting the rail to the sleeper. The rail is fixed with respect to the framework through bolts or wedges.

US-A 1.260.148 relates to a U shaped structure whose webs are provided with shoulders to springly engage, through bolts the rail head of the rail within the cavity.

According to the invention all these drawbacks are eliminated by a rail element in particular for subway, tramway and railway tracks, as described in claim 1.

The present invention is further described hereinafter with reference to the accompanying drawings, in which:

Figure 1: is an exploded perspective view of a rail element according to the invention;
Figure 2: is a cross-section thereof;
Figure 3: schematically shows the connection between two rail elements;
Figure 4: is a schematic plan view of a switch formed from the rail element of the invention;
Figure 5: is a cross-section therethrough on the line V-V of Figure 4; and
Figure 6: is a cross-section therethrough on the line VI-VI of Figure 4.

As can be seen from the figures, the rail element of the invention comprises substantially a monolithic iron body 2 of substantially H-shaped cross-section, closed lowerly to form a chamber 4 and provided externally with two appendices 6 for its fixing to support plates 7 and shaped substantially as the support flanges of traditional rails.

Said monolithic body 2 comprises two sidepieces 8 forming a seat 10 for housing the head 12 and the counterblade 14, constituting the wheel contact elements.

The head 12 and counterblade 14 are fixed to the box body 2 by bolts 16 inserted through slotted holes 21 of larger diameter, foreseen in the horizontal portion 24 of the body 2, and engaging in nuts 19 after interposing a bush 32 and a coil spring 23.

Gaskets 29 of self-adhesive rubber are interposed between the outer surface of the head and/or the blade and the inner surface of the box seat.

The interior of the chamber 4 can be filled with sound-absorbent material 20.

To mount the rail element on the roadway, the monolithic body 2 is embedded in the roadway 33 and welded to the adjacent elements to create a continuous structure. Each H-shaped element may be welded to plates 7 which have the same purpose as traditional sleepers. Preferably the plates 7 rest on an insulating anti-vibration layer.

The rolling element (head 12 and counterblade 14) is then inserted into the seat 10 and is fixed to the base by the bolts 16. The butt joint between adjacent elements is made at an angle of 45° to the cross-section.

In a preferred embodiment (shown in Figure 3, in which the box structure is not embedded in the roadway) the space between the two H-shaped elements can be provided with reinforcements and filled with concrete, or can be covered with a continuous plate 25 to provide a seat for the passage of cables and/or manifolds.

From the aforegoing it is apparent that the rail element according to the invention has numerous advantages, and in particular:

it enables the head and counterblade to be easily replaced in accordance with programmed maintenance at very low cost compared with the cost of installing the entire rail, in that it necessitates merely the removal of the worn parts without involving the road surface, hence avoiding long traffic interruptions and all the discomfort connected therewith;
it enables the removable element to be constructed of a different material than the structure itself, which material can be of greater strength and moreover is not subject to any limitation regarding welding, as is the constituent material of the monolithic body;
it presents high sound absorption by virtue of the filling of the internal chamber 4;
it enables the profile of the removable elements to be effectively restored, as this can now be done directly in the workshop;
it enables antiwear weld material to be effectively applied, as this can now be done directly in the workshop using suitable material and adequately preheating if required;
presents a greater stability of fixing the rail to the box body and avoids any problem relating to possible thermal and/or mechanical deformation of the bolt 16 engaged in nut 19.

Figures 4-6 (which don't show bolts according to the present invention) illustrate a rail 33 prolonged by a switch 34 for directing a vehicle either onto the rail 35 or onto the rail 35'. The switch 34 consists of a piece shaped upperly to form a seat 36 for housing the switch tongue 38, the two corresponding stock rails 40, 40' and the section bar 41 directly in contact with the heel 43 of the tongue 38. The two stock rails 40, 40' and the section bar 41 are fixed to the base of the seat 36 by traditional bolts 42, whereas the switch tongue 38 is screwed to the box body in correspondence with the heel 43 and slides with its toe 45 on the base of said seat via an interposed plate (not shown on the drawings) of antiwear material.

The interior of the chamber 4 is filled with sound absorbent material and can also house traditional electrical resistance heater elements (not shown on the drawings) to ensure movement of the switch tongue even in the coldest weather.

Although the invention has been described with reference to a switch, the deviation element can also be used for cross-overs, in which case the movable elements are in the form of a single profiled piece comprising two crossing groves.

In a further embodiment (not shown in the drawings) of the invention it is foreseen that, due to a possible displacement of the switch tongue in a space near the front end of the heel and the facing end of the switch tongue, which displacement could cause a wear in this zone, the heel is hinged near the end facing the adjacent rail and is elastically biased to follow the displacement of the switch tongue.

Claims

A rail element in particular for subway, tramway and railway tracks consisting of a substantially H-shaped continuous monolithic box structure (2), to be embedded in the roadway (33) so that the upper surfaces of the vertical portions of the H-shaped box structure are at the same level as the road surface, the horizontal portion (24) of said structure defining with the upper vertical portions a seat for removably connecting the wearable wheel guide element (12,14,38,40,40'), the bond between the guide element and the horizontal portion being obtained through a plurality of bolts (16) which pass through slotted holes (21) provided in said horizontal portion (24) and having a diameter larger than the diameter of the bolts, said bolts (16) engaging a nut (19) after interposition of a bush (32) and a coil spring (23).
An element as caimed in claim 1, characterised in that the wheel guide element consists of a head (12) and a counterblade (14).
An element as claimed in claim 1, characterised in that the structure (2) is of iron material, and is closed at its bottom end to form a chamber (4).
An element as claimed in claim 3, characterised in that the chamber (4) is filled with sound absorbent material (20).
An element as claimed in claim 4, characterised in that the interior of the chamber (4) houses manifolds for conduits and/or cables.
An element as claimed in claim 1, characterised in that the structure is prolonged externally into two appendices (6) shaped substantially as the support flanges of traditional rails.
An element as claimed in claim 2, characterised in that the head (12) and the counterblade (14) are formed in separate pieces.
An element as claimed in claim 2 characterised in that between the outer surface of the head (12) and/or the blade (14) and the inner surface of the box seat rubber gaskets (29) are interposed.
An element as claimed in claim 1 characterised in that the box structure is welded to plates (7), having the same purposes as traditional sleepers.
An element as claimed in claim 9 characterised in that the space between two parallel box structures is covered with a continuous plate (25).
An element as claimed in claim 1, characterised in it consists of a switch (34) and in that the guide elements consist of a tongue (38), two corresponding stock rails (40, 40') and a section bar (41) directly in contact with the heel (43) of the tongue (38).
An element as claimed in claim 1, characterised by consisting of a cross-over, the guide elements consisting of a shaped piece comprising two crossing grooves.
An element as claimed in claim 11, characterised in that the stock rails (40, 40') are fixed to the base of the seat (36) by bolts (42), the movable tongue (38) being screwed to the structure at the heel (43).
An element as claimed in claim 13, characterised in that the tongue (38) slides with its toe (45) on a plate of antiwear material.
An element as claimed in claim 14 characterised in that the heel (43) is hinged near the end facing the adjacent rail and is elastically biased to follow the displacement of the switch tongue.