EP0051338B1 - Method and means for measuring the position of a railway rail - Google Patents

Abstract

1. A method of measuring the position of a railway track for checking, correction and/or recording purposes, by using a measuring vehicle travelling on the rails and a measuring base that is determined by rail reference points (A, C, D) and is defining the theoretical course of the rails, whereby the position of at least one measuring point (B) on the rail is determined relative to said measuring base, characterized in that use is made of a reference line (s) independent of any points (A, B, C, D) situated on the rails (2, 3) and extending at least approximately in the longitudinal direction of the rails, said reference line (s) being secured to at least one fixed point (A') of the vehicle (1) and defining a reference system independent of said measuring base and said measuring point (B), the co-ordinates of said rail reference points (A, C, D) and said measuring point (B) relative to said reference system are measured, whereafter on the one hand the measuring base resulting from the co-ordinates of said rail reference points (A, C, D) and on the other hand using the co-ordinates of the measuring points (B) the deviation of these measuring points (B) from said measuring base are calculated.

Description

The invention relates to a method and a device for detecting the position of the rails of a railway track for the purposes of checking, correcting and / or recording, using a mobile measuring or working vehicle. moving on the rails as well as a measurement base which is determined from rail reference points and which defines the theoretical route of the rail, which makes it possible to determine the position of at least one measurement point on the rail relative to the measurement base.

The methods of devices known hitherto in the field of track surveying, in particular for carrying out rail correction works, have the common feature that the distance between a point on the rail or working is always determined directly and a measurement base, the latter being represented by a reference material element, either straight or curvilinear, in the form of wires, rods or the like (cf. patents GB-A-1423574, AT-A-305 333, DE -A-2818405). These reference material elements must be arranged and constructed in such a way that they coincide as exactly as possible with the reference points of the rails, or are constantly at a fixed distance from them. The rail reference points are notoriously defined using special measuring instruments which equip the measuring and / or working vehicle, or by means of measuring trolleys rolling on the rails at a determined distance in front of or behind the vehicle. In this case, the precise mounting and alignment of the reference elements on, above or below the measuring or working vehicle constitute a source of serious drawbacks, above all because of the space required. Furthermore, as a general rule, it is difficult to avoid, during the measurement operations, certain variations in the position of the reference elements relative to the reference points of the rails which determine the measurement base.

Whereas, to level a rail, you need a rectilinear base of measurement, and that to rectify or align laterally a rail in a curve you generally need a measurement base in the shape of an arc of a circle, until now, to carry out these two measurement or correction operations, respectively provide two separate measurement bases on the measurement or work vehicle. To define a straight line as a measurement base, you must have a reference point on the rail, in a section of track which has not yet been corrected, as well as a reference point in a section of track. which has already been corrected, while in order to define an arc of a circle as a measurement base in a curved rail part, in addition to a reference point located in a track section not yet corrected, at least two points of reference sities in a section of track already corrected.

It is also known to use a measurement method in which one operates with an optical goniometer which is located at the measurement point and whose optical axis serves as a reference line, as well as with a light source located at the measurement points. rail reference and whose position relative to the optical axis is determined by angular measurement (see patent CH-A-510,171). In this case, it is essential to mount the optical goniometer either exactly at the measurement point, or at a constant and known distance from this point.

The invention aims to solve the problem posed by the realization of a simple method to implement for the measurement of the rails, and in which the need to represent the measurement base defined by means of the reference points of the rails is eliminated. by means of a reference material element or by the use of a light ray or an optical axis of an element, while allowing the execution of simultaneous leveling and alignment measurements, as well as possibly the determination and recording of many other parameters relating to the rails.

To solve this problem, the method according to the present invention is characterized in that a reference line independent of all reference points on the rails is used, this reference line extending at least approximately in the longitudinal direction of the rails. and being fixed to at least one fixed point of the vehicle so as to constitute a reference system independent of the measurement base and of the measurement point; that the coordinates of the reference points of the rails and of the measurement points are measured in relation to this reference system, and that on the one hand, from the coordinates of the reference points of the rails, the measurement base is calculated and, on the other hand, from the coordinates of the measurement points, their deviation from the measurement base is calculated.

This avoids having to reproduce the measurement base by material elements which concretely connect the reference points of the rails to one another or having to keep them at a fixed distance from the points of the rails, which is inconvenient for the from the point of view of assembly and above all ensures only an imprecise positioning, and one succeeds, by simply using known measuring instruments, especially instruments designed to measure lengths and goniometer, to determine each position of all the important points along the rails with respect to the reference line defined on the measuring or working vehicle and which is independent of the reference points on the rails. Consequently, the measurement method according to the present invention is particularly flexible, since as a general rule and undoubtedly many arbitrary reference points can be taken into account in that it is necessary to have recourse to a material reference element covering all of these reference points. In addition, it is possible, using a single reference line, to simultaneously carry out all the measurement operations which are necessary to carry out a track measurement process and to make the necessary correction of the rails, in particular leveling, alignment and bearing measurements and the desired rail parameters can be determined using a suitably programmed automatic computer. In addition, according to the invention, it is also possible, after a channel correction and without resorting to any auxiliary means, to measure and record directly under the parameters which make it possible to control the quality of the work performed. This registration, which is generally required by the Railway Administration, has hitherto required special measurement operations and special arrangements of particular instruments. In general, this involves recording the following six parameters: elevation, deformation, bearing (boom height) in the horizontal and vertical planes, as well as total lifting and lateral displacement total of the rails, that is to say the corrections made by moving the rails between the position they occupied before the correction and that they occupy after this correction. Optionally, other parameters can also be determined for checking the track layout.

The device for implementing the method is characterized in that the reference line is constituted by a rectilinear reference element which is either an integral part of the chassis of the vehicle, or fixed or tensioned with respect to this chassis, this element being at least one electromagnetic ray emitted by a source of radiation fixed to the chassis of the vehicle, or from an optical axis of an optical instrument fixed to the chassis of the vehicle; that measuring means comprising a pendulum are installed at the measuring and reference points of the rails, and arranged so as to measure the coordinates of all the points of the aforementioned rails in a reference system which is defined across the line of reference and the vertical passing through this reference line, preferably in the vertical plane containing this reference line, and finally an automatic computer is provided for processing all the quantities measured.

In the other patent claims, advantageous embodiments of these devices are described. The reference element can be a stretched wire, a fiber, a string or the like. It is recommended to make sure that the element which constitutes the reference line, or the liminous radius which takes its place, is protected from external atmospheric agents; if a light ray is adopted, it must be protected against weakening or rupture due to fog or humidity. Preferably, a hollow spar will be used for this, which generally comprises the chassis of the measurement or work vehicle, to surround the reference element or the light ray or rays emitted by a light source.

• La figure 1 est une représentation schématique illustrant le principe du procédé suivant l'invention dans un premier mode de réalisation;
• la figure 1 a est une variante de procédé de ce mode de réalisation, dans le cas de la mesure d'un point sur le rail;
• la figure 1 b est une extension du procédé de l'invention dans laquelle on utilise quatre points de référence des rails;
• la figure 2 est un système de référence défini par la ligne de référence;
• les figures 3 à 10 montrent des détails relatifs à un dispositif pour la mise en oeuvre pratique du procédé illustré par les figures 1 à 3;
• les figures 11 et 12 montrent schématiquement des dispositifs opérant avec des rayons lumineux en tant que lignes de référence;
• la figure 13 montre schématiquement un dispositif dans lequel la ligne de référence est définie par l'axe optique d'un goniomètre optique;
• la figure 14 montre schématiquement la réalisation d'une base de mesure presque absolue en rapport avec l'invention;
• la figure 15 montre schématiquement un second mode de réalisation du procédé de l'invention et
• les figures 16 à 18 montrent des détails relatifs à un dispositif se rapportant à ce second mode de réalisation.

The invention will now be described in more detail with reference to the drawings. On these:

• Figure 1 is a schematic representation illustrating the principle of the method according to the invention in a first embodiment;
• FIG. 1a is a variant of the method of this embodiment, in the case of the measurement of a point on the rail;
• FIG. 1 b is an extension of the method of the invention in which four reference points of the rails are used;
• Figure 2 is a reference system defined by the reference line;
• Figures 3 to 10 show details of a device for the practical implementation of the method illustrated in Figures 1 to 3;
• Figures 11 and 12 schematically show devices operating with light rays as reference lines;
• FIG. 13 schematically shows a device in which the reference line is defined by the optical axis of an optical goniometer;
• FIG. 14 schematically shows the production of an almost absolute measurement base in relation to the invention;
• FIG. 15 schematically shows a second embodiment of the method of the invention and
• Figures 16 to 18 show details of a device relating to this second embodiment.

Figure 1 shows the principle of the method according to the invention. On a measurement or work vehicle 1, designated without further details, and which rolls on rails 2 and 3, a straight reference line is defined which extends in the longitudinal direction of the vehicle 1, or of the rails. For this purpose, a cruex spar 4 is used, oriented in the longitudinal direction and which is generally found on the chassis of a vehicle of this kind, and in this spar the straight line which connects the central points A 'and C 'of the two end faces 5 and 6 of the beam, constitutes the reference line s. For this, it can be a question, as will be seen in more detail below, either of a straight line materialized by a taut reference element, for example a wire, a fiber or the like, or of an immaterial straight line consisting of an optical axis of an optical device or instrument, or of a light ray or a beam of another type of electromagnetic radiation.

Below the end faces 5 and 6 there is provided a measuring mechanism or chassis comprising measuring wheels or feeler rollers rolling on the rails 2 and 3, and the points of contact with these rails define the reference points A and C of the rails. The two reference points A and the point A ', on the one hand, and the two reference points C and the point C', on the other hand, lie in a plane oriented perpendicular to the reference line s . Another measurement mechanism, located at any point in the middle of the vehicle, defines with its measurement wheels rolling on the rails the measurements made at the respective points B on the two rails 2 and 3. A pendulum 30 incorporated in each measurement mechanism is used to measure the inclination of the wheel axis and to define the vertical independently of the momentary orientation of the measuring vehicle 1 or the spar 4. This gives the definition of a three-dimensional reference system thanks to the vertical plane containing the reference line s, as shown in Figure 2. For simplicity, we naturally choose an orthogonal coordinate system, the origin of which is for example at point A ', and which has the axes x, y and s shown in Figure 2. Thus, one can tilt the vehicle 1 or the beam 4 relative to the verticle, that is to say by deviating from the y axis of Figure 2 at an angle 8 measured by pendulum 30.

The reference line s is only defined through the two points A 'and C' and independently of any other point on the rails. The purpose of a rail survey is to determine the difference between a measurement point B on the rails and a measurement base defined by the reference points A and C of these rails, which represents the theoretical profile of the rails. . In the case of leveling of a straight track section, the measurement base will naturally be a straight line which passes through the reference point A which is on a track section which has not yet been corrected and by the reference point C which is on the already corrected section of track. While up to now the distance between the measurement point B and the line connecting the reference points A and C was determined directly using a reference element representing this straight line AC, we now define according to the invention first the coordinates of the reference points A and C as well as the measurement point B in the system defined by the reference line s and independent of all the reference points of the rails. From the coordinates thus measured, the respective deviations of the measurement points B from the measurement base defined by the reference points A and C are then calculated, using an automatic computer mounted on the vehicle 1.

To measure the aforementioned coordinates of the reference points A and C, respective measuring means have been installed at the end faces of the beam, in planes orthogonal to the reference line s and which contain the points A 'and C' , to measure the triangles AA'A and CC'C which are in these planes. Since we know the distance h between the sides arranged face to face of the annular flange wheels of the mobile measuring mechanism, and consequently the distance AA or CC, therefore the base of the triangle, it is now sufficient to measure the two other triangles a1 and a2 or c1 and c2 using two instruments to measure the lengths. Alternatively, one could also measure using a goniometer the angle a or y at point A 'or C' between the adjacent sides of the triangles and, using an instrument to measure the lengths, those of two adjacent sides of triangles a1 or a2, or c1 or c2. We thus obtain for example for the triangle AA'A the three known quantities h, a1, a2 or h, α, a 1, or even h, α, a2, from which, based on known trigonometric ratios, in finds the position of points A 'and C' with respect to reference points A or C, and therefore in relation to the usual measurement bases.

The position of the measurement point B relative to the reference line s results from the measurement of the two triangles which are both in the same transverse plane of the beam 4 which is perpendicular to the reference line s and contains the measurement point B. A triangle is located inside the spar 4 and is defined by its apex B ', which is on the reference line s and by the point of intersection of said plane with the two lower edges of the spar 4, of which the distance from point B 'is designated by the symbols b' 1 and b'2. The other triangle is located under the spar 4 and is defined by the two measurement points B of the rails and the point of intersection B "which is in the middle of the lower side of the spar; the sides of the triangle which are adjacent to this intersection point B "are equal to the width i of the beam 4 and therefore they are known. To measure these interior triangles it is necessary to also provide two length measuring instruments to measure the length of the sides b 'and b'2, or else a single length measuring instrument which measures one of these two sides, as well as a goniometer to measure the angle of intersection f31 at point B '. Similarly, to measure the lower triangle whose base h is known, either two length measuring instruments which effectively measure the sides b1 and b2 are used, or a single length measuring instrument which measures one on these two sides, as well as a goniometer to measure the angle of intersection b2 at point B ". Whereas the spar is more or less inclined with respect to the plane of the rails, or can also be chopped, we will determine the angle, formed by the lower side of the side member with one side, for example the side b 1, of the lower triangle, using another goniometer for this purpose. of trigonometric or geometric relations the position of the measurement point B with respect to the reference line s 2.

FIG. 1a shows a variant of the measurement arrangement intended to determine the position of the measurement point B in relation to the reference line s. Instead of the lower triangle BB "B according to FIG. 1, a square will be measured according to the arrangement of FIG. 1 having a side h, which corresponds to the distance between the flanged measuring wheels of the measuring mechanism, a side i, which corresponds to the width of the spar 4, as well as the sides b "and b" 2, which connect in pairs the end points of the two sides mentioned above. To measure this square, four measuring instruments are required, which measure the length of the two sides b "1 and b" 2 as well as the two angles (33 and (34.

FIG. 1 b schematically shows the method according to the invention in the case where it is necessary to have in the uncorrected track section of the new one the reference point A and in the already corrected track section two pairs of reference points C and D located at a known distance between them. Three reference points A, C and D for the construction of a circular arc as a measurement base will be necessary to measure or align a curved track in a curve. In this case, the reference point D and the point D 'are in the transverse plane containing the rear end face of the beam 4, while the reference point C and the point C' which are in front of said plane are contained in a transverse plane of the beam 4 which is located between the measurement points B and the reference point D and can be measured with the same accuracy as the measurement points B, in accordance with the explanations given above with reference to FIG. 1 .

FIGS. 3 to 10 show a first embodiment for implementing the method according to the invention, in which the reference line s is produced in the form of a wire 7 which extends inside a hollow spar 4 of the vehicle chassis. Instead of a wire, one can of course also use a fiber, a string or the like. In what follows we will only refer, in general, and for the sake of clarity, to a thread 7.

From Figure 3, we see that there is provided a tube 8 disposed in the center of the beam 4 and in the longitudinal direction thereof, and along its axis extends a wire 7 representing the reference line s. At its two ends, this tube 8 is held in anchor blocks 9 and 10 fixed and centered near the end faces 5 and 6 of the spar 4 by means of stop screws 11 (FIG. 8) screwed into the wall of the spar, where a reinforcing strip 12 is provided all around the spar. At the first end 5 of the spar 4 the end of the wire 7 which emerges from the tube 8 is anchored to a guide pin 13, which passes through an opening provided in the center of the end wall 5 of the spar and abuts with its end adjacent to this end wall 5 against an anchoring block 9. At the other end face 6 of the spar, the wire 7, as shown in FIG. 8, is fixed to the rod 14 of the piston 15 of a hydraulic cylinder 16 which is housed in the extension of the tube 8 in the anchor block 10. When the piston 15 is subjected to a pressurized fluid, the wire 7 is tensioned with a predetermined force. The interior of the tube 8 can be filled, by means of a filling connector 16a shown in FIG. 3, with a liquid having the same density or approximately the same density or density as the reference element 7, if one uses advantageously in this case, for reasons of weight, a textile thread but not a metallic thread. This dampens the wire's oscillations and vibrations. On the external face of the cylinder 16 and in the extension of the wire 7 is fixed a guide pin 17 which jointly defines the first guide pin 13 at the other end of the beam 4, the axis, outside this beam, of the reference line s. To these guide pins 13 and 17 are applied measuring devices provided at points A and C and which, in the illustrated embodiment, consist of two length measuring instruments, intended to measure the length of the sides of triangles a1 and a2 as well as c1 and c2 mentioned above. As shown in FIG. 8, the two length measuring instruments 20 and 21 are mounted in rotation by means of ball bearings 22 and 23 on the guide pin 17 to measure the distances c1 and c2. Similarly, on the guide pin 13 are also mounted in rotation, by means of corresponding ball bearings, the two instruments 18 and 19 for measuring the lengths to measure the distances a 1 and a2. The other ends of the length measuring instruments 18, 19 and 20, 21, also visible in FIGS. 4, are articulated on the wheel axles of the two measuring mechanisms which are located at the reference points A or C, and as shown FIG. 9 for the two length measuring instruments 18 and 19 as well as the axle 24 of the measuring wheels 25, which belong to the measuring mechanism 26 and define the reference points A of the rails. The measuring mechanism 26 comprises a guide system with two rods 27 arranged in a V, which are articulated on a support 26a fixed to the chassis of the vehicle and can, by means of a lifting device 28 acting on a cross member 29 connecting these two rods 27 between them, be raised when the vehicle has to be moved from one zone to another. On the axle of the wheel 24 is fixed in pendulum 30 to measure the inclination of the measuring mechanism relative to the vertical in a plane oriented perpendicular to the rails. The measuring mechanism located at measuring points C as well as at the measurement points B can be carried out exactly like the measurement mechanism 26.

The measuring means shown in Figures 3, 6 and 10 at the measuring point B comprises a measuring system installed under the beam 4 and a measuring system installed inside this beam 4. The lower system consists, in the example shown, of two length measuring instruments 31 and 32 (FIG. 6) which connect point B "according to FIG. 1 with the two measuring points B defined by the corresponding measuring wheels and is used to measure the distances or sides of triangle b1 and b2 according to Figure 1. These length measuring instruments can pivot at their upper end around a pivot represented by point B ", while their lower end is articulated on the axle of the wheels of the mechanism corresponding measure. In addition, a goniometer 33 is arranged on the aforementioned axis to measure the angina p according to FIG. 1. The internal measurement system, shown diagrammatically in FIG. 10, is mounted inside an anchoring block 34, which is made like the anchor blocks 9 and 10, and keeps the tube 8 correctly centered. The internal measurement system, in the area of which the tube 8 has an interruption, also consists in the example shown, of two instruments 35 and 36 for measuring the lengths, the upper ends of which, thanks to an eyelet 37, surround the stretched wire. 7 and whose lower ends are articulated on pivots 38 mounted in the lower corners of the anchor blocks 34.

One of the instruments 31 or 32, 18 or 19 as well as 20 or 21 for measuring lengths can also be replaced by a goniometer at points B ″, A ′ and C ′, as indicated in the description of the process according to l with the invention with reference to Figures 1 and 1 a.

When the tube 8, as seen above, is filled with liquid, it is advantageous to provide the wire 7, which in this case constitutes the reference line s, with cross fins, as shown in the figure 10. Preferably, of course, several of these stabilizing or damping elements 39 could be provided along the wire 7, and this preferably at each wave belly of the wire 7. Thanks to these measures, the oscillations and vibrations are largely damped wire 7. When a liquid is present in the tube 8, the interior of the anchor blocks 34, with respect to which sections of the tube 8 are fixed or tightly adjusted, can also be filled with this liquid.

Thanks to this arrangement of the wire or fiber 7 and to the various planned measurement arrangements, it is obtained that possible deformations of the spar 4, such as bending or twisting, practically have only a negligible effect on the measurements carried out. Thus, thanks to the articulated mounting of the instruments 18, 19, 20 and 21 for measuring the lengths on guide pins 13 and 17, the effects of the torsion of the spar 4 are eliminated, and thanks to the internal measurement system provided in the plane. transverse of the beam 4 at point B ', each position of the beam 4 is measured relative to the wire or fiber 7, which is modified by deformations of said beam. With the measurements described, it is possible to determine all the coordinates of the reference points A and C, as well as those of the measurement points B in the reference system, which is defined by means of the wire or fiber 7, and consequently by the vertical plane which contains the reference line s, which is the xy plane according to figure 2.

There is shown schematically in Figure 7 the measurement system which is located below the beam 4 in the case of a measurement carried out in accordance with the arrangement of Figure 1a. In this example, the upper ends of two instruments 40 and 41 for measuring lengths are articulated on two pins 42 and 43 mounted on external projections of the beam 4. In addition, there are provided on the aforementioned projections measuring instruments d angle or goniometers 44 and 45 which serve to measure the angle indicated at f33 and f34 in FIG.

Preferably, one could provide inside the beam 4, as shown in Figure 3, other reinforcing elements 46 with radial orientation. It is advantageous to produce the tube 8 together with the wire 7 by the hydraulic cylinder 16 incorporated in this tube in the form of a complete assembly which can be slid as necessary in the beam 4, fix in an adjustable manner in the blocks d anchor and extract at will from these.

In the description given so far of the method of the invention, the dimension h between the flanges of the measuring wheels 25 of a measuring mechanism, and therefore the spacing between the two rails, have been considered to be constant values. In this case, the measuring mechanisms are generally biased by a jack mounted on the vehicle chassis against one of the two rails, so that at all times each of the measuring wheels constantly carries on one side with its annular flange against the corresponding rail. All measurements and corrections therefore have these rails as their basis. If, however, the gauge of the track is not exactly constant, and varies slightly from one place to another, which is particularly possible in the case of wooden sleepers whose material works over time, it is in principle preferable to carry out measurements and corrections along the axis of the track, therefore to carry out an alignment along this axis. In this case, the dimension h will not be taken as a constant but as a variable and measured using a measuring mechanism whose measuring wheels can slide along the axis of the wheels and are constantly solicited in the direction of distance one on the other by a spring or a jack, so that their tubes bear constantly and simultaneously against the two rails. An instrument 47 for measuring the lengths, shown in phantom in Figure 9 and mounted on the axle of the measuring wheels 25, is used to measure the generally variable spacing between the rails 2 and 3. From this measured value of h it is easy to take all the measurements on the axis of the track and therefore carry out a correction along this axis.

In the example shown in Figure 11 the reference line s is constituted by a light ray 50 emitted by a light source 51 along the axis of the spar 4, this source being located at A 'on the end face 5 of the spar above the rail reference points A. In a plane oriented perpendicular to this light ray 50 and passing through the measurement point B there is provided a transparent optical detector 52 comprising several photoelectric cells, preferably four in number, distributed radially and on the opposite end face 6 of the spar il is provided at C ', above the reference points C of the rails, an optical detector 53 of the same type, but not transparent in this case. Thanks to these optical detectors 52 and 53 of a type known per se and which are fixed to the spar 4, it is possible to determine deviations from the centers of these detectors, which would be due to possible deformations of the spar, according to the direction of the light ray 50. The detectors 52 and 53 may possibly be replaced by instruments operating with light-sensitive CCD matrices. At the reference points A and C, as well as, under the spar 4, at the measurement points B, the same measurement means are arranged as those described above with reference to FIGS. 3 to 9, and which are used to measure each position of the track or track points relative to the reference system defined by the light ray 50.

In the example according to FIG. 12, the reference line s consists of the light rays 55 and 57 oriented towards one another and emanating from two respective light sources 56 and 58 installed opposite one of the other on the two end faces 5 and 6 of the spar, ie at points A 'and C'. In this case, in the plane perpendicular to the light rays and containing the measurement points B are installed at B ', two optical detectors 59 and 60 of the above-mentioned type, intended to receive one and the other respectively of the light rays directed towards these detectors so as to allow the position of the beam 4 to be measured in the above-mentioned plane with respect to the reference line thus defined by the light rays, and consequently possible deformations of said beam.

FIG. 13 schematically shows an embodiment given by way of example, in which the reference line s is formed by the optical axis 61 of an optical goniometer of known type and which coincides with the axis of the spar 4, this instrument being mounted at A 'on the end face 5 of the spar, above the reference points A of the track. In planes orthogonal to the optical axis 61 and which contain on the one hand the measurement points B of the track and on the other hand the reference points C of the track, the inside of the spar has been fixed light sources 63, 64 and 65, 66 which emit light rays directed towards the optical angular measurement instrument or goniometer 62. The latter constantly measures the angle formed between the optical axis 61 and these light sources. For a determined arrangement of the light sources, the value of these angles is known when the beam 4 is not deformed, and they determine the points B 'and C' which are on the optical axis 61 above the points B of measurement of the rails or of the reference points C of the rails in the above-mentioned plane. Deformations of the beam 4 result in corresponding modifications of the angles formed between the optical axis 61 and the light rays and are therefore determined according to the angular value measured. At reference points A and C and at measurement points B, there are also provided, as shown in FIGS. 3 to 9, measuring means for reading the respective positions of the track points with respect to the reference system defined according to the optical axis 61. The optical instrument 62 for measuring the angles can be constituted in particular by the apparatus described in patent AT-PS-312,025 for determining the angle of at least two light rays which intersect between them at one point.

In the example according to FIG. 14, a so-called almost absolute measurement base is used. For this purpose there is provided, at any distance from the actual measuring or working vehicle 1, a mobile independent measuring carriage 70 which moves at least approximately at the average speed of the vehicle 1, defines a reference point A _o situated far ahead and further carries a light source 71. On the front face of the vehicle 1 is provided a measuring means 72 which defines the reference line s in any way on this vehicle 1. This means comprises on the one hand a rangefinder operating by electromagnetic radiation in order to determine the distance from the light source 71 and, therefore, the reference point A _o , and on the other hand a goniometer, for example of the type described in the aforementioned patent AT- PS 312 025, by which the angle ε, therefore the angular position of the reference point A _o with respect to the reference line s on the vehicle 1, can be calculated. The measuring instruments carried by the vehicle 1 at the track points designated in A, B, C, D and E in FIG. 13 can be produced exactly like those of the other embodiments described above. Rail reference points D and E could be embodied by a measuring cart rolling behind the vehicle 1 on the rails, and connected thereto by a control rod, in order to measure the orientation of this measuring cart relative to the vehicle 1 and, therefore, by relative to the beam 4 provided with the reference line.

Figures 15 to 18 refer to another embodiment of measuring devices installed at the track points A, B, C and D and possibly at other points located on the track, by means of which the coordinates of these reference points of the rails in a different way compared to what the measuring devices according to Figures 1 to 10 allowed. With devices according to Figures 1 to 10, the distances or angles were measured for the construction of triangles AA'A, etc. (figure 1), so that from these measurement data and using trigonometric functions we can calculate the coordinates of the track points A, B, etc. in a Cartesian coordinate system comprising the reference line s or the points A ', B', etc.

The configuration of the measurement means according to FIGS. 15 to 18, on the other hand, makes it possible to directly measure the coordinates necessary in a Cartesian system of coordinates ^x _A , ^y _A ; x _e , Y _B ; x _c , Y _c and x _a , y _D , which, as shown schematically in Figure 15, are obtained in each transverse plane of the spar 4 located at track points A, B, C and D. Here it is Cartesian systems of relative coordinates which are perpendicular to the axis of the spar 4 and therefore to the reference line s and, as shown in FIG. 16 for the measurement means at reference points A of the track, these coordinates are materialized by a T-shaped part fixed to the longitudinal member 4 and comprising a vertical arm 73 and a cross member 74. The longitudinal direction of the cross member 74 norma! e-ment arranged horizontally defines the axis or the direction x, while the normally vertical arm 73, which is perpendicular to said cross member, designates the direction y. The origin of this coordinate system is the point A ', which is on the wire 7 forming the reference line s, which also extends there inside the tube 8 along the axis of the spar 4 .

The coordinates y of the reference points A on the rails, namely the points of contact between the measuring wheels 25 and the rails 2 and 3, will be measured according to FIG. 16 using two instruments 75 and 76 to measure the distances, which are articulated on the one hand on each end of the cross member 74 at the point of articulation 80 or 81, and on the other hand on the axis 24 of the mobile measuring carriage, near the wheels 25, more precisely at the location of pivots 82 and 83. The x coordinate will be measured using an instrument 77 for measuring the lengths, which is articulated on the one hand on the lower end of the arm 73 at the pivot point 84, and on the other hand to the aforementioned pivot 83 of the length measuring instrument 75. Whereas the coordinate system rotates with the spar 4 around the latter's axis, if for example there is a deformation or a torsion of this spar 4 its angular position relative to the vertical will be determined using 'a pendulum 78 arranged at point A', which makes it possible to measure the coordinates of points A in the reference system defined by the above-mentioned wire 7 and the vertical plane which contains this wire 7.

FIG. 15 shows the normal wheels 95 of the measurement vehicle which advances in the direction of the arrow, as well as the measurement wheels 25; the rear reference points D of the track will be defined by the rear wheels of the actual measuring carriage 97 which rolls on the rails and which is fixed by a drawbar 96 to the chassis or the side member 4 of the measuring vehicle, which determines the position of this mobile measuring carriage relative to the beam 4. The coordinates measured in the various coordinate systems, which are therefore determined in each case in the transverse planes of the beam 4 which pass through the points of rails A, B and C, are indicated in FIG. 15. In each direction x are the values x _e , x _b and x _c which are determined using the length measuring instrument 77 (FIG. 16) or the analog measuring instruments of other measuring systems. In the directions y are the values y _a1 , y _b1 and y _c1 , for the left measuring wheel (in the direction of travel) on rail 2, and the values y _ar ; y _br and y _cr for the right wheel (always in the running direction) on rail 3. These coordinates will be measured by the length measuring instruments 75 and 76, as well as by the analog measuring instruments of the other measuring means .

All the measurement means comprise, apart from the pendulum 78 according to FIG. 16, corresponding pendulums with which the angles designated in δ _A , 8 _B , δ _c . or δ _D in FIG. 15 will be measured, these angles being formed between on the one hand the longitudinal axis of the arm 73 of FIG. 16 and the other corresponding arm, that is to say each y axis of the different systems coordinates, and on the other hand the vertical. In the event of deformation of the beam 4, all these angles can have different values, in other words, the different relative coordinate systems can have a different orientation between them.

In the event of significant deviations between the points noted on the rails and the normal values, which these points can reach in their coordinate system, consequently and for example in the event of significant sliding of the reference points A of the tracks according to figure 16 , a modification of the x coordinates, therefore of the length measuring instrument 77, risks generating an error in the y coordinates measured, and vice versa. To avoid this inconvenience, one end of each of the length measuring instruments according to FIG. 16 and of the length measuring instruments 75, 76 and 77, instead of being articulated simply on an articulation axis, is slidably mounted along the curve of a cam correction 79, against which this end of the measuring instrument concerned abuts. This curve is a cardioid.

In the transverse plane of the spar 4 which contains the measurement point B of the track, its bending will again be measured relative to the wire 7, and for this it is preferable to measure the relative slip between the spar 4 and the wire 7 in the same system of relative coordinates x _e , _YB (Figure 15), as discussed above. An advantageous arrangement which is suitable for the measurement in question inside the beam 4 is shown in FIG. 18 and includes a measurement system 85 for measuring the displacement in the y direction and a measurement system 86 of exactly the same design but arranged with a angular offset of 90 degrees around the axis of the wire 7 for measuring the displacement in the x direction. The two systems are arranged perpendicular to the direction of the wire 7. The description which follows only refers to the measuring system 85, the components of which are designated by reference numbers in FIG. 18. A straight guide rod 87 oriented in the direction y, mounted to slide freely in bearings 88, is made integral at its ends by plates 84 and 89 of the movable core 90 of an instrument 91 for measuring lengths which is therefore arranged parallel to the guide rod 87. This instrument 91 for measuring lengths is of a design known in this technical field, according to which no physical contact is produced between the core 90 and the body of the instrument. A cursor 92 integral with the guide rod 87, which extends perpendicularly to the latter, therefore in the x direction, surrounds the wire 7 with its two arms. The entire measuring system 85, as well as the another measurement system 86 is rigidly fixed by screws 93 to the spar 4 or to the wall of an anchor block fixed inside this spar, according to the arrangement of the blocks 34 of FIG. 10. Each movement of the wire 7 parallel to the rod 87 is transmitted to the instrument 91 and measured by the latter, while a movement in the direction perpendicular to this rod 87 has no effect. Similarly, each movement of the wire 7 in the x direction will be perceived and transmitted by the cursor of the other system 86.

When the method of the invention is used for track correction work and, consequently, the measurement and reference means are installed on a track straightening machine equipped with roller or roller clamps for leveling and erecting the rails, it may be advantageous if the measuring points B of the track or rails constitute the points of attack of the roller clamps. Another advantageous possibility, with regard to the choice of track measurement points B in the case of a working vehicle or a track straightening machine equipped with a ballast tamping device, lies in the fact that the measurement points of the rails, located just in front and behind the tamping device which may include one or more sets of tamping picks, can be constituted by measuring wheels or probes and that the coordinates measured according to these track measurement points can be used to calculate an average rail measurement point between these points that would almost coincide with the location of the tamping tools. This solution is convenient because it is obvious, for practical reasons, that it is impossible to use the tamping tools themselves to define the measurement points of the rails.

As a general rule, it is required by the administration, in the work of rectifying the tracks, in the bus to control the quality of the corrections made, to record the six parameters set out above which until now had to be determined separate measurements and in general by special means of measurement after the completion of correction or rectification work. According to the present invention, these six parameters can be determined and recorded directly by the same equipment installed on the work vehicle, therefore by the same reference systems and the same measurement means, and by adopting the same measurement methods as those used. for the quantities necessary for the correction, so that this recording is carried out each time immediately after the execution of a rectification operation. This requires at least three track reference points, arranged one after the other in the rectified track section, which can be the reference points C, D and E in Figure 14. It is however also possible to operate only with the two rear reference points C and D which are necessary for the calculation of the channel correction, the third reference point used being the measurement point B located immediately after the correction, considered before the work vehicle moving forward. In this way, each measurement or working point B of the rails can serve, immediately after rectification, as a new reference point in the corrected track section for the measurement of the aforementioned parameters which must be recorded, so that it is sufficient provide on the work vehicle, behind the measurement points B or behind the tamping tools, simply two reference points of the rails C and D, arranged one behind the other.

The method and the devices according to the invention are also extremely flexible, as demonstrated by the examples of embodiment. tion described and the foregoing explanations, and allow in a rational manner, by means of a suitably programmed automatic computer, to carry out the measurements and / or calculations of all the quantities and of all the necessary parameters. For this purpose, the measuring means can be constituted by measuring instruments known per se, whereby one can use, as apparatus for measuring the lengths, for example instruments operating with electric linear potentiometers. The invention is in no way limited to the exemplary embodiments described, because on the contrary these lend themselves to numerous variants, in particular as regards the construction and the arrangement or realization of the reference lines which define the reference system as well. as the arrangement of the measurement means.

Claims (18)

1. A method of measuring the position of a railway track for checking, correction and/or recording purposes, by using a measuring vehicle travelling on the rails and a measuring base that is determined by rail reference points (A, C, D) and is defining the theoretical course of the rails, whereby the position of at least one measuring point (B) on the rail is determined relative to said measuring base, characterized in that use is made of a reference line (s) independent of any points (A, B, C, D) situated on the rails (2, 3) and extending at least approximately in the longitudinal direction of the rails, said reference line (s) being secured to at least one fixed point (A') of the vehicle (1) and defining a reference system independent of said measuring base and said measuring point (B), the co-ordinates of said rail reference points (A, C, D) and said measuring point (B) relative to said reference system are measured, whereafter on the one hand the measuring base resulting from the co-ordinates of said rail reference points (A, C, D) and on the other hand using the co-ordinates of the measuring points (B) the deviation of these measuring points (B) from said measuring base are calculated.

2. A method according to claim 1, characterized in that a single and same reference system defined through said reference line (s) is used for simultaneously carrying out the measurements necessary on the one hand for levelling and on the other hand lining the rails, and in addition, subsequent to the correction operations, for measuring and recording all important rail parameters for checking the quality of the corrections.

3. A device for carrying out the method according to any of claim 1 or 2, characterized in that said reference line (s) consists of a rectilinear element (7) which is either an integral part of the vehicle chassis, or fastened or tensioned thereon, of either at least one electromagnetic ray (50, 55, 57) emitted from at least one radiation source fastened to the vehicle chassis, notably a light source (51, 56, 58), or of an optical axis (61) of an optical apparatus (62) secured to the vehicle chassis, in that measuring means including a pendulum (30, 78) being mounted at the level of all the rail reference and measuring points (A, B, C, D), and arranged such that the co-ordinates of all the aforesaid rail points (A, B, C, D) included in a reference system are measured which is defined by said reference line (s) and the vertical given by said pendulum (30, 78), preferably the vertical plane containing said reference line (s), and in that the assembly comprises an automatic computer for calculating all the measured magnitudes.

4. A device according to claim 3, comprising a measuring or working vehicle of which the chassis comprises at least one longitudinally oriented hollow beam, characterized in that said reference line (s) extends within said beam (4).

5. A device according to claim 4, characterized in that said reference line (s) consists of a reference element (7) in the form of a yarn, fibre or the like secured to and tensioned at either transverse end face (5, 6) of said beam (4), in that below both end faces (5, 6) rail measuring wheels (25) defining reference points (A, C) rest on the rails (2, 3), in that each end face (5, 6) of the beam (4) has fitted thereto one of said measuring means (18, 19, 20, 21; 75, 76, 77) and in that in at least one cross-sectional plane of the beam (4) containing the measuring points (B) and being located between said end faces (5, 6) of the beam (4) measuring means are disposed comprising measuring instruments (31, 32, 33; 35, 36; 85, 86) installed externally and internally of said beam (4), and so arranged as to measure in said cross-sectional plane of the beam (4) on the one hand the position of the beam (4) relative to the measuring points (B) and on the other hand the position of said reference element (7) relative to said beam (4).

6. A device according to claim 5, characterized in that the measuring means provided at the end faces (5, 6) of said beam are each pivotally mounted to a pivot guide pin (13, 17) axially aligned to said tensioned reference element (7) and rotary in a plane perpendicular to said reference element (7) and containing the rail reference points (A, C) so as to measure the distance between said guide pins (13, 17) and said rail reference points (A, C), in that the internal measuring means (35, 36) disposed in the cross-sectional plane of said beam (4) and passing through said rail measuring points (B) are so arranged as to measure the distance between the reference element (7) and two points located inside said beam, and in that said external measuring means (31, 32, 33; 40, 41, 44, 45) disposed in said last-mentioned cross-sectional plane are so arranged as to measure the distance between at least one point of said beam (4) and said rail measuring points (B).

7. A device according to claim 5, characterized in that all the measuring means comprise only instruments for measuring lengths (75, 76, 77, 91) so mounted and oriented as to measure directly the co-ordinates of the rail points (A, B, C, D) in a relative cartesian coordinate system (X_A, Y_A; X_e, YB; ... such a system being fixed on said beam (14) in each one of its cross-sectional planes passing through said rail points.

8. A device according to any of claims 5 to 7, characterized in that the reference element (7) extends along the axis of a tube (8) held in a centered position within said beam (4) by means of a plurality of anchoring blocks (9, 10, 34).

9. A device according to any of claims 5 to 8, characterized in that said reference element (7) has one end fastened to a piston (14, 15) of a pressure-fluid actuated cylinder (16) and being in that way subjected to a predetermined constant pulling force.

10. A device according to any of claims 8 or 9, characterized in that the inner space of said tube (8) is filled with a liquid for damping out any oscillation of the reference element (7), said fluid having at least approximately the same specific weight as said element (7).

11. A device according to claim 10, characterized in that said reference element (7) is provided with at least one radial oscillation- damping fin (39).

12. A device according to any of claims 8 or 9, characterized in that said tube (8) constitutes an interchangeable unit incorporating said reference element (7) tensioned therein, and possibly said pressure-fluid actuated cylinder (16), said unit being adapted to be interchangeably introduced into or removed from said beam (4).

13. A device according to claim 4, characterized in that the reference line (s) consists of a light ray (50) emitted from a light source (51) installed at one end face (5) of said beam and in that a transparent optical detector (52), for example composed of several radially distributed photocells or of a CCD-Matrix is disposed in a plane orthogonal to said light ray (50), and another optical detector (53) of same type is disposed at the opposite end face (6) of said beam.

14. A device according to claim 4, characterized in that said reference line (s) consists of the light rays (55, 57) emitted from two light sources (56, 58) directed towards each other and fitted in face-to-face relative arrangement at the two end faces (5, 6) of said beam, respectively, and in that two optical detectors (59, 60) intended for one light ray and for the other light ray, respectively, are disposed in a plane orthogonal to said light rays and containing said measuring points (B), said detectors being adapted for example through a plurality of radially distributed photocells or through CCD-Matrix, to measure the position of said beam (4) in said plane relative to the reference line (s) defined by said light rays.

15. A device according to claim 4, characterized in that the reference line (s) consists of the optical axis (61) of an optical goniometer (62) fitted to one of the end faces (5) of said beam, two light sources (63, 64, 65, 66) being secured to said beam (4) above said measuring point (B) and to the opposite end face (6) of said beam, respectively, in such a way that their light rays are directed towards said goniometer, respectively.

16. A device according to any of claims 3 to 15, characterized in that it comprises - in order to provide a nearly absolute measuring base - an independent movable measuring carriage (70) rolling on the track rails (2, 3) at any suitable distance from the main measuring or working vehicle proper (1), said carriage defining a front reference point (A_o), and in that a special measuring arrangement (72) being installed on said main measuring or working vehicle (1) and so arranged as to be capable of measuring the position of a characteristic point, notably a light source (71), disposed on said measuring carraige (70), in relation to the reference system defined by said reference element (s), and comprising preferably a telemeter operating by electromagnetic radiation and an optical goniometer, for measuring the distance to said light point (71) of said measuring carriage (70) and its angular position relative to said reference line (s).

17. A device according to any of claims 3 to 16, disposed on a track correcting machine provided with roller tongs for levelling and lining the rails, characterized in that said rail measuring points (B) are the operating points of said roller tongs.

18. A device according to any claims 3 to 16, mounted on a working vehicle equipped with at least one track tamper, characterized in that the rail measuring points (B) are provided just ahead and behind the tamper and in that the measured co-ordinates are utilized for calculating an average rail measuring point located therebetween.

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