EP0145919B1 - Device for continuously reprofiling the head of at least one rail - Google Patents

Abstract

The device for reprofiling the head of at least one rail comprises a support (1, 2, 12, 13, 9) carrying at least one grinding unit (3, 4, 6, 7) pivotally mounted about an axis (8) extending parallel to the longitudinal axis of the rail (11). This grinding unit has a grinding wheel (3) driven in rotation by a motor (4) and structure (7) for displacing axially the grinding unit (3) to apply it against a side line of the head of the rail (11) and thus compensate its wearing off. It comprises structure (9, 10, 19, 20, 21) for displacing the axis of pivoting (8) of the grinding unit (3, 4, 6, 7) parallel to itself, in a direction transverse to the longitudinal axis of the rail (11). Servo-mechanism is provided to make dependent on each other the pivoting of the grinding unit (3, 4, 6, 7) and the displacement of its axis of pivoting (8).

Description

Machines using pivoting grinding units controlled are currently used for reprofiling the rails because it is thus possible to reduce the number of grinding wheels necessary and therefore to make compact machines. These machines with controlled pivoting grinding units, as described in patents CH 606,616 or CH 633,336, have in particular the drawback of requiring, during each angular adjustment of the position of the grinding wheel, to reposition the grinding wheel against the rail to be ground. In addition, the angular amplitude of the pivoting of the grinding units is limited.

It is also known from GB-A-1,151,010 a device for reprofiling the fungus of at least one rail comprising a support carrying at least one grinding unit, pivotally mounted about an axis parallel to the axis longitudinal of the rail, having at least one grinding wheel driven in rotation by a motor and means of axial displacement of this grinding wheel to apply it against a generator of the rail head and thus compensating for its wear. This known device also comprises means for moving the pivot axis of the grinding unit, parallel to itself, in a direction perpendicular to the longitudinal axis of the rail.

The problem which currently arises for rail reprofiling machines is to be able, with the same grinding wheel, to grind both the face, the internal leave and the rolling table as well as the face and external leave of the rail. This is particularly essential when preparing the rails for the railing. With existing machines, this can only be done with long manual adjustments and bulky grinding units, their axial stroke, parallel to the axis of rotation of the grinding wheel, having to be large. Finally, these large axial strokes affect the precision of grinding.

The object of the present invention is therefore to produce a machine in which the grinding wheel (s) can pivot by a large angle, of approximately 180 °, that is to say by a much greater angle than on existing machines, while avoiding that during its pivoting, the grinding wheel does not come into conflict with the obstacles it might encounter on the way, such as fishplates, lag screws, etc. In addition, to ensure good quality of the grinding, it is necessary to avoid that a change of inclination of the grinding wheel does not entail a significant correction of its axial position, parallel to its axis of rotation, to bring it back into contact with the rail. .

The subject of the present invention is a reprofiling device comprising the characteristics listed in claim 1.

• La figure 1 est un schéma illustrant la trajectoire du centre de la surface active de la meule lors du pivotement de l'unité de meulage autour de son axe qui est parallèle à l'axe longitudinal du rail.
• La figure 2 est une vue de côté, partielle, d'un chariot porte-meules suivant une première forme d'exécution.
• La figure 3 est une vue partielle de dessus du dispositif illustré à la figure 2.
• La figure 4 est une vue en bout du dispositif illustré à la figure 2.
• La figure 5 est une vue semblable à la figure 4 d'une seconde forme d'exécution du dispositif.
• La figure 6 illustre schématiquement une troisième forme d'exécution du dispositif.

The accompanying drawing illustrates schematically and by way of example three embodiments of the device according to the invention.

• FIG. 1 is a diagram illustrating the trajectory of the center of the active surface of the grinding wheel when the grinding unit is pivoted about its axis which is parallel to the longitudinal axis of the rail.
• Figure 2 is a partial side view of a grinding wheel carriage according to a first embodiment.
• FIG. 3 is a partial top view of the device illustrated in FIG. 2.
• FIG. 4 is an end view of the device illustrated in FIG. 2.
• Figure 5 is a view similar to Figure 4 of a second embodiment of the device.
• Figure 6 schematically illustrates a third embodiment of the device.

Figure 1 shows schematically the principle of moving a grinding wheel according to the present invention. To obtain the desired result, either rotate the grinding wheel 180 ° while keeping it in contact with the rail or, when the latter is deformed, in its immediate vicinity, the center 0 of the active surface of the grinding wheel along line A while causing the grinding wheel to rotate about an axis parallel to the longitudinal axis of the rail. The center of the active surface moves in 01, 02, 03, 04 and 05 successively for successive angular positions of the grinding wheel offset by 45 ° in the example illustrated, but this active surface of the grinding wheel always remains in contact or at immediate proximity to the rail head. Such movement of the grinding wheel 3 can be obtained by the combination of a rotation of the grinding unit about an axis parallel to the longitudinal axis of the rail and a movement of this pivot axis, parallel to itself, in a direction perpendicular to the longitudinal axis of the rail 11.

The first embodiment of the device for the continuous reprofiling of the head of at least one rail of a railway track comprises a carriage 1 provided with flanged wheels 2 which are preferably applied without play against the rails using adequate resources. This carriage 1 is thus guided longitudinally and transversely by the rails and is connected to a rail vehicle (not shown) by means ensuring traction. This carriage 1 is also connected to the rail vehicle by lifting means causing relative displacements in height between the carriage 1 and the rail vehicle.

On this carriage 1, at least one grinding unit is mounted so as to be angularly movable relative to the latter about an axis substantially parallel to the longitudinal axis of the rail. Each grinding unit comprises a grinding wheel 3 driven in rotation by a motor 4 sliding with the aid of slides 5 on a yoke 6 parallel to the axis of rotation of the grinding wheel 3. This axial rectilinear movement of the grinding unit allows to apply it with. a determined force against the surface of the rail head and to compensate for its wear. A jack 7 connects the yoke 6 to the motor 4 and thus allows the wheel 3 to be applied against a generator of the rail to be ground with a determined force causing it to move. axial to compensate for the wear of the grinding wheel.

The yoke 6 comprises two concentric pins 8, constituting the pivot axis of the grinding unit, pivoted in a slide 9 sliding on transverse guide bars 10 of the carriage 1, that is to say extending perpendicularly in the longitudinal plane of symmetry of the carriage and therefore of the rail 11 to be ground.

These guide bars are connected to cross members 12 of the carriage, themselves fixed to the central beams 13 of the chassis of said carriage 1.

In this way the grinding unit 3, 4, 7 is mounted on the carriage 1 so as to pivot around an axis parallel to the longitudinal axis of the rail; this pivot axis being movable parallel to itself in a direction perpendicular to the axis of said rail. In the example illustrated, this displacement of the axis perpendicular to the axis of the rail 11 is rectilinear but in variants it could be linear, curvilinear or other.

In the example illustrated, the grinding unit 3, 4, 7 comprises means for driving the latter in its pivoting movements around the axis materialized by its two pins 8. These means comprise a toothed wheel 14 , integral with a pin 8, engaged with a helical screw 15 journalled in the slide 9 and driven in rotation for example by a stepping motor 16. These means may also include, as in the example illustrated, a sensor 17 supplying an indicator i of the angular position of the helical screw 15 relative to the slide. This angular indication corresponds to the inclination of the grinding unit 3, 4, 7 relative to the carriage 1.

An electromagnetic brake 18 can be provided to lock the grinding unit in a given angular position, which is necessary so that the angular position of this grinding unit is fixed during a grinding operation in the selected position corresponding to the grinding of a determined generator of rail 11.

In the example illustrated, the grinding unit 3, 4, 7 also comprises means for moving the pivot axis of the grinding unit comprising a screw 19 cooperating with a part 20 fixed to the cross member 12 of the carriage forming nut. This screw is pivoted in the holes of the slide 9 but cannot move axially relative to the latter: A stepping motor 21 drives the screw 19 in rotation and moves the slide 9 along its guide bars 10.

One can also provide a sensor for determining the angular position of the screw 19 and therefore the position of the slide 9 relative to the carriage 1, as well as an electromagnetic blocking of the screw to fix the position of the slide 9 relative to the carriage 1.

Means are provided for slaving between them the pivoting of the grinding unit and the movement of its pivot axis. In this embodiment, these means are constituted by an electrical synchronization device S of the two stepping motors 16 and 21 so that the angular displacements of the grinding unit and the displacement of its pivot axis are such that the center 0 of the active surface of the grinding wheel 3 follows the line A of FIG. 1. In this way the grinding wheel 3 can pass from a horizontal position to a vertical position, its active surface always remaining substantially at the same distance from the surface of the rail head 11, or even in contact with it.

Thanks to this arrangement and to the rotational and translational displacements of the grinding unit, the axial stroke of the grinding wheel is practically reduced to the axial stroke necessary for compensating for the wear of the grinding wheel and for positioning it. removal, out of service. Under these conditions, the size of the grinding unit is greatly reduced and therefore the guidance of the grinding wheel is more precise.

Note that according to the concept of the invention, the grinding wheel 3 has four degrees of freedom; pivoting about the pivot axis 8 of the grinding unit; a translation of this axis 8 in a direction perpendicular to the longitudinal axis of the rail, an axial displacement in the direction of the rail and a rotation about its own axis.

In a variant, it is obvious that for reasons of guiding the grinding unit in its translation and pivoting movements, two translational drives 19, 20, 21 and two pivoting drives 15, 16 can be provided, respectively. on either side of the slides 5.

In a simplified embodiment, it is possible to use a single motor driving in rotation the helical screw controlling the pivoting of the unit and the screw controlling the displacement of the pivot axis of this unit. These two screws could have come from a single workpiece. In this case, the combined movement, translation - pivoting of the grinding unit is entirely determined by construction and according to the profile of the rail head the grinding wheel remains at a substantially constant distance from said rail head during its movements. The advantage of this solution lies in the simplicity of the means for driving the grinding unit in pivoting and in translation.

In the second embodiment illustrated in FIG. 5, the mounting of the grinding unit 3, 4, 7 on the carriage 1 is the same as in the first embodiment, only the drive means of the unit in its pivoting and driving the pivot axis of the grinding unit in its movements, are different.

The pivoting of the grinding unit 3, 4, 7 around its pins 8 is obtained by means of a jack 22 fixed on the slide 9, actuating a rack 23 engaged with a pinion 24 integral with the journal 8. A sensor 25 delivers an indication relating to the inclination of the grinding unit as a function of the linear position of the piston of the jack 22.

The drive of the pivot axis in its movements and in the translation of the grinding unit is carried out using a jack 26, fixed on the carriage, the piston of which actuates the slide 9 along the guide bars 10. A position sensor 27 delivers an indication of the position of the slide 9 relative to the carriage 1 to a position indicator i.

Here also a servo device S causes the cylinders to be supplied with working fluid in a synchronized manner so that the center 0 of the active surface of the grinding wheel 3 follows the path A illustrated in FIG. 1 so that for all the inclinations from the grinding wheel its distance from the rail head remains substantially constant.

In a third embodiment schematically shown in Figure 6, the grinding unit 3, 4, 7 sliding in the yoke 6 is pivotally mounted via the pins 8 of the yoke 6 on the free end of levers 32 the other end of which is pivoted on the crosspieces 12 of the carriage 1. These levers are actuated in angular framings around their articulation on the crosspieces 12 by jacks 33 fixed to the carriage and the piston of which is connected to the middle part of the lever 32.

In this embodiment the pin (s) 8 are integral with toothed wheels 28 meshing with the internal toothing of toothed rings 29 which they are integral with the carriage.

Thus in this embodiment, a desmodromic connection is produced between the pivoting of the grinding unit and the displacement of its pivot axis which here always takes place parallel to itself and in directions perpendicular to the axis of the rail 11 but following a circular and no longer straight path. In such an embodiment, the number of teeth of the crowns 29 and of the toothed wheels 28 is such that the center of the active surface of the grinding wheel 3 travels along the path A of FIG. 1 during the angular displacements of the levers 32.

In general, we see that according to the invention it is possible to rotate a grinding wheel so that it can act on the entire surface of the head of a rail while maintaining its distance from the head of the rail substantially constant, even resting on this rail if the advance cylinder 7 is under pressure. In addition, which is also very important, the area swept by the grinding wheel during its movements does not interfere with fishplates 30, lag screws 31 or any other obstacle that may be along or near the rail.

This result is obtained in accordance with the invention in that the grinding unit is mounted on its support carriage so as to be able to pivot around an axis parallel to the longitudinal axis of the rail and so on the other hand that its pivot axis jointly undergoes a translation perpendicular to the longitudinal axis of the rail.

In variants, it is possible to combine two grinding units which would then be driven by the same drive means in pivoting and in translation.

The grinding units can include grindstones, lapidaries or peripherals.

All the embodiments described relate to the continuous grinding and on track of the rails of a laid railway track. However it is obvious that the reprofiling device can be mounted on a fixed support and provide means causing the displacement of a rail relative to this support. In this way, it is possible to reprofile all kinds of rails in the factory.

Claims (8)

1. Device for reprofiling the head of at least one rail (11) comprising a support (1) carrying at least one grinding unit, pivotally mounted around an axis (8) extending parallel to the longitudinal axis of the rail (11), having at least one grinding wheel (3) driven in rotation by a motor (4) and means (5, 7) for axially displacing said grinding wheel (3) to apply it against a side line of the head of the rail (11) and thus compensating its wearing off, as well as means for (9, 10) displacing the axis (8) of pivoting of the grinding unit, parallel to itself, in a direction perpendicular to the longitudinal axis of the rail (11), characterized by the fact that it comprises servo- control means (S) of the pivoting of the grinding unit and of the displacement of its axis (8) between themselves, and by the fact that the motor (4) of each grinding unit is slidably mounted, parallel to the axis of rotation of the grinding wheel (3), on a joke (6); the means (5, 7) for axially displacing the grinding wheel (3) being located between the motor (4) and the joke (6) and permitting to slide them the one with respect to the other.

2. Device according to claim 1, characterized by the fact that each grinding unit is pivoted on a sliding block (9) mounted on slides (10) carried by the support (1); these slides (10) extending perpendicular to the longitudinal axis of the rail (11).

3. Device according to one of the preceeding claims, characterized by the fact that it comprises driving means (14, 15, 16) of the grinding unit in its pivoting movement comprising a motor (16), as well as the means displacing the axis of pivoting of said grinding unit; and by the fact that the servo-mechanism (S) synchronises the two motors (16, 21) so that for a pivoting of about 180° of the grinding wheel (3), the distance of said grinding wheel with respect to the rail (11) remains substantially constant.

4. Device according to claim 1, characterized by the fact that the grinding unit is linked to the support (1) by means of a desmodromic linkage synchronising the pivoting of said grinding unit and the displacement of its axis of pivoting (8) and by the fact that only one motor (33) drives the grinding unit simultaneously in its conjugated displacement of pivoting and translation.

5. Device according to one of the preceeding claims, characterized by the fact that the means driving the grinding unit in its movement of pivoting and/or of displacement of its axis of pivoting comprise displays of the position (i) of this grinding unit.

6. Device according to one of the preceeding claims, characterized by the fact that it comprises further locking means of the grinding unit in its different working positions.

7. Device according to one of the preceeding claims, characterized by the fact that the support is formed by a carriage (1) longitudinally and transversally guided by the rails (11) of a railroad track, and that it comprises means connecting this carriage to a railroad vehicle driving it along the track and lifting means causing relative displacements in height between the carriage and the railroad vehicle.

8. Device according to claim 7, characterized by the fact that it comprises means maintaining flanged wheels (2) of the carriage (1) in lateral contact with the rail (11) to guarantee a guiding of the carriage (1) on the track without play.

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