[0001] This invention relates to a device and a method for applying lubricating grease to
the mobile blades of railway points.
[0002] A problem particularly felt in the railway sector is that of wear on rails following
the passage of trains. That problem manifests itself in particular at curved stretches
where the lateral thrust of the wheel on the rail is particularly high and, therefore,
where friction between the two is at its maximum.
[0003] To overcome the problem over the years many devices have been developed which can
apply lubricant on the rail at the most critical points.
[0004] In particular, the first automatic lubricating devices were devices able to apply
lubricating oil. In most cases they were mounted close to the rail, at a distance
allowing the train wheel to pass, and applied the oil by spraying it onto the rail.
[0005] The main disadvantage of that type of device is that it cannot guarantee an adequate
lubricating effect because the oil, having a low viscosity, tends to run down the
side of the rail and is wasted.
[0006] Therefore, to overcome that disadvantage solutions were developed which were able
to automatically apply lubricating grease to the rail. In particular, initially solutions
were developed in which the grease, like the oil, was dispensed by spraying, such
as that described in patent
EP 787 638. However, subsequently, to guarantee improved application of the grease, the Applicant
provided a device able to apply a strip of lubricating grease to the rail, described
in patent
EP 1 999 000. Said device comprises a mobile nozzle which on one hand can be moved close to the
rail when it must dispense the grease and distanced from the rail when a train must
pass, and on the other hand is able to move along a predetermined stretch of rail.
[0007] However, at present none of the prior art devices has proved able to lubricate another
point of the railway lines which is particularly subject to wear, the blades of the
points. In fact, all of the prior art devices must be able to be installed in a very
precise way at a predetermined distance from the part to be lubricated. But that is
quite complicated with the blades of points, which are not fixed like the rails, but
instead are mobile. In particular, lubricating devices cannot be positioned close
to the blade when it is in the operating position because they would prevent its subsequent
movement. At the same time, they cannot be positioned with the required precision
when the blade is in its non-operating position, because it is not possible to guarantee
that this position is always the same. Moreover, the prior art devices have dimensions
which in many situations would complicate their positioning near the set of points.
[0008] Tests have shown how for the blades too, adequate lubrication requires the use of
lubricating grease rather than oil.
[0009] Consequently, at present, the blades are only lubricated manually.
[0010] In this context, the technical purpose which forms the basis of this invention is
to provide a device and a method for applying lubricating grease to the mobile blades
of railway points which overcome the above-mentioned disadvantages.
[0011] The technical purpose and the aims indicated are substantially achieved by a device
and a method for applying lubricating grease to the mobile blades of railway points
as described in the appended claims.
[0012] Further features and the advantages of this invention are more apparent in the detailed
description, with reference to the accompanying drawings which illustrate several
preferred, non-limiting embodiments of a device and a method for applying lubricating
grease to the mobile blades of railway points, in which:
- Figure 1 is a schematic front view of a device made in accordance with this invention,
coupled to a set of points (in turn shown in cross-section) whose blade is in the
operating position;
- Figure 2 illustrates the device of Figure 1 with the blade of the set of points in
the non-operating position;
- Figure 3 is a view, partly in cross-section, of an alternative embodiment of part
of the device of Figure 1;
- Figure 4 is a schematic axonometric view of a detail of the devices of the previous
figures;
- Figure 5 is a schematic top section of a part of the detail of Figure 4.
[0013] With reference to the accompanying drawings, the numeral 1 denotes in its entirety
a device for applying lubricating grease to the mobile blades 2 of railway points
3 made in accordance with this invention.
[0014] Figure 1 schematically illustrates a cross-section of a part of a set of railway
points 3. The set of points 3 comprises a base 4, fixed to a sleeper 5 below by sleeper
screws 6, to which the stock rail 7 is fixed by conventional fixing systems 8. Resting
on a raised flat bearing of the base 4 there is the blade 2, which can move between
the operating position of Figure 1 in which it is drawn near the stock rail 7, and
the non-operating position of Figure 2 in which it is distanced from the stock rail
7.
[0015] According to this invention, the lubricating device 1 comprises first a supporting
structure 9. Advantageously, in the preferred embodiment, the supporting structure
9 can be fixed directly to the base 4 of the set of railway points 3, as shown in
Figures 1 and 2, so as to guarantee that it remains stably and precisely positioned.
In particular, this can be achieved by fixing the supporting structure 9 to the base
4 of the set of points 3 directly using one or more sleeper screws 6 which fix the
base 4 to the sleeper 5 below. Alternatively the lubricating device 1 may be suitably
fixed to the sleeper or to the stock rail (for example with brackets or clips).
[0016] In the embodiments illustrated, the supporting structure 9 comprises a plurality
of shaped flanges 10 (extending perpendicularly to the plane of the drawing of Figures
1 to 3) which are connected to each other. In particular, in the embodiment in Figures
1 and 2 there is one T-shaped and two L-shaped flanges 10 which are welded to each
other. In contrast, in the embodiment in Figure 3 they are connected to each other
by a plurality of bolts 11 inserted through aligned slots 12 which are made in the
flanges 10. Therefore, in this case, the position of the various flanges 10 relative
to each other may be modified in such a way as to be able to adjust the position in
space of the operating part of the device 1 (advantageously in a plane substantially
perpendicular to the direction of extension of the stock rail 7).
[0017] The device 1 also comprises at least one applicator element 13 mounted on the supporting
structure 9, designed to apply grease to the blade 2. In particular, the applicator
element 13 comprises a contact portion 14 against which in practice the blade 2 of
the set of railway points 3 can rest 2 when it is in its non-operating position, as
shown in Figure 2.
[0018] Finally, the device 1 comprises feed means 15 for feeding the lubricating grease
to the contact portion 14. In general, in the known way, the feed means 15 comprise
a tank for the grease, a pump whose intake inlet is connected to the tank and whose
delivery outlet is connected to a dispensing duct 16 whose other end is in turn connected
to the applicator element 13. In the accompanying drawings only the duct is shown.
[0019] The principle on which this invention is based is that the grease is transferred
from the applicator element 13 to the blade 2 after the blade 2 has come to rest against
the contact portion 14 of the dispensing element. For that purpose, the feed means
15 may, for example, be made in such a way that they distribute the grease on the
contact portion 14 before the blade 2 rests on it.
[0020] However, in the preferred embodiment (Figures 4 and 5), the contact portion 14 comprises
a contact surface 17 able to adhere to a lateral surface of the blade 2 and at least
one recess 18 made in the contact surface 17. The recess 18, which in Figure 4 has
the shape of a slot at the contact surface 17, in practice can be positioned directly
opposite the blade 2, and is fed with the grease by the feed means 15, in such a way
that it can be substantially filled with the grease. As shown in Figure 5, in the
embodiment illustrated this is achieved using passages 19 made in the applicator element
13 and connected to the dispensing duct 16. However, preferably the mouths 20 of the
recesses have an elongate shape parallel with what in practice is the direction of
extension of the blade 2.
[0021] Advantageously, at least the portion 21 of the applicator element 13 which forms
the contact surface 17 is made of elastically compressible material (for example,
rubber), in such a way that it adheres in the best possible way to the wall of the
blade 2, creating a certain seal as the grease passes around the open mouths 20 of
the recesses.
[0022] Preferably, as illustrated in the accompanying drawings, the applicator element 13
is mounted on the supporting structure 9 in such a way that it can move, relative
to the supporting structure, between a home position (Figures 1 and 3) and an operating
position (Figure 2). In the embodiment illustrated this is done by fixing, cantilever-style,
to the applicator element 13, two parallel rigid rods 22 with the outer end 23 enlarged
to act as an end of stroke element. The two rods 22 are slidably inserted in two bushings
24, welded to one of the flanges 10 of the supporting structure 9.
[0023] In the embodiment illustrated, in the home position the applicator element 13 is
distanced from the supporting structure 9, whilst in the operating position it is
close to it.
[0024] Advantageously, the applicator element 13 is mounted on the supporting structure
9 in such a way that the pressure of the blade 2 on the contact portion 14 causes
the applicator element 13 to pass from the home position to the operating position.
[0025] As shown in the accompanying drawings, there are also preferably elastic means 25
interposed between the supporting structure 9 and the applicator element 13 for pushing
the applicator element 13 towards the home position in the absence of the blade 2.
In the particular case illustrated the elastic means are two coil springs mounted
so that they are coaxial with the rods 22 supporting the applicator element 13, between
the applicator element and the supporting structure 9. Thanks to the elastic means
25 the device 1 can therefore compensate in the best possible way for any irregular
positioning of the set of points 3.
[0026] Finally, in the most complex embodiments, the device 1 also comprises at least one
sensor 26 for detecting the presence of the blade 2 resting on the contact portion
14, as well as control means 27 which are operatively associated with the sensor 26
and with the feed means 15 for enabling grease feed according to what the sensor 26
detects. In general, the sensor 26 may be a contact sensor 26 (for example, mechanical)
or a contactless sensor (for example, electromagnetic, as shown in the accompanying
drawings, or optical or ultrasonic).
[0027] Operation of the feed means 15 depends on the device 1 operating logic.
[0028] In the case illustrated, the control means 27 activate the feed means 15 when the
sensor 26 detects the presence of the blade 2, in such a way as to fill the recesses
18 with the grease which therefore makes contact with the lateral surface of the blade
2 which closes off the recesses 18. Consequently, when the blade 2 returns to its
operating position, it draws with it part of the grease, partly emptying the recesses
18.
[0029] However, operation could be different if the grease were dispensed directly onto
the contact portion 14. In that case, the control means 27 would issue the command
to dispense a predetermined quantity of grease at the moment when the sensor 26 detected
the absence of the blade 2.
[0030] In the absence of the sensor 26, the feed means 15 could instead be activated periodically
at predetermined time intervals.
[0031] Obviously, this invention also relates to a set of railway points 3 equipped with
the applicator device 1 described above.
[0032] The method for applying lubricating grease to the blades 2 of railway points 3 comprises
two main operating steps.
[0033] The first operating step comprises applying the grease on at least one part of the
surface to be greased while said surface is resting on a contact portion 14 of an
applicator element 13, in such a way that the next time it returns to its operating
position the blade 2 carries with it at least part of the grease with which it made
contact. This can be achieved, for example, with the device 1 described above in any
of the ways indicated.
[0034] The other main operating step comprises putting the blade 2 in contact with the applicator
element 13, making at least part of its surface to be greased rest on the contact
portion 14 of the applicator element 13, at the moment when the blade 2 is in its
non-operating position, precisely as indicated with reference to the greaser device
1 described above.
[0035] The other steps of the method according to this invention are those which in practice
are implemented by the device 1 described above, which implements a possible embodiment
of the method.
[0036] This invention brings important advantages.
[0037] Thanks to this invention, it was possible to provide a device which is simple to
make and whose cost is quite limited, which guarantees correct greasing of the blade.
[0038] The invention described above may be modified and adapted in several ways without
thereby departing from the scope of the inventive concept.
[0039] Moreover, all details of the invention may be substituted with other technically
equivalent elements and the materials used, as well as the shapes and dimensions of
the various components, may vary according to requirements.
1. A device for applying lubricating grease to the mobile blades of railways points,
characterised in that it comprises:
a supporting structure (9);
at least one applicator element (13) mounted on the supporting structure (9) and comprising
a contact portion (14) against which in practice a blade (2) of a set of railway points
(3) can rest when the blade is in its non-operating position; and
feed means (15) for feeding the grease to the contact portion (14).
2. The device according to claim 1, characterised in that the contact portion (14) comprises a contact surface (17) which is able to adhere
to a lateral surface of the blade (2), and also comprises at least one recess (18)
made in said surface and which in practice can be positioned directly opposite the
blade (2), the feed means (15) being connected to the recess (18) in such a way that
they can feed grease to it.
3. The device according to claim 1 or 2, characterised in that the applicator element (13) comprises at least one portion forming the contact surface
(17), made of elastically compressible material.
4. The device according to claim 1, 2 or 3, characterised in that it also comprises at least one sensor (26) for detecting the presence of the blade
(2) resting on the contact portion (14), and control means (27) operatively associated
with the sensor (26) and with the feed means (15) for enabling grease feed according
to what the sensor (26) detects.
5. The device according to claim 4, characterised in that the sensor (26) is an electromagnetic, optical, mechanical or ultrasonic sensor (26).
6. The device according to any of the foregoing claims, characterised in that the applicator element (13) can move relative to the supporting structure (9) between
a home position and an operating position, the pressure of the blade (2) on the contact
portion (14) causing the applicator element (13) to pass from the home position to
the operating position.
7. The device according to claim 6, characterised in that it also comprises elastic means (25) interposed between the supporting structure
(9) and the applicator element (13) for pushing the applicator element (13) towards
the home position in the absence of the blade (2).
8. The device according to any of the foregoing claims, characterised in that the feed means (15) comprise a tank for the grease, a pump connected to the tank
and to a dispensing duct (16) which is in turn also connected to the applicator element
(13).
9. A set of railway points, characterised in that it comprises an applicator device (1) made according to any of the forgoing claims.
10. A method for applying lubricating grease to the blades of railway points which are
mobile between an operating position in which the blades are in contact with a stock
rail (7) and a non-operating position in which they are distanced from it,
characterised in that it comprises the operating steps of:
when the blade (2) is in its non-operating position, bringing it into contact with
an applicator element (13), resting at least part of its surface to be greased on
a contact portion (14) of the applicator element (13);
using the applicator element (13) to apply grease on at least part of the surface
to be greased while it is resting on the contact surface (17), so that when it subsequently
returns to its operating position the blade (2) carries with it at least part of the
grease with which it made contact.