US3136065A - Arrangement for aligning railroad tracks - Google Patents

Description

June 9, 19 F. PLAS SER ET AL ARRANGEMENT FOR ALIGNING RAILROAD TRACKS Filed March 3, 1961 IN V EN TORS Jose"? EUR ER KGEMT United States Patent 3,135,065 ARRANGEMENT FQR ALEGNING RAKLRQAD TRAQKS Franz Plasser and Josef Theater, oath of .l ehannesgasse 3, Vienna 1, Austria Fiied Mar. 3, 1961, Ser, No. 93,256 Claims priority, application Austria Mar. '7, W60 3 Claims. (Cl. 33-456) This invention is concerned with the grading of railroad tracks, and more particularly with controlling a desired superelevation of one rail of a track section by means of a line of reference.

It is well known to establish a line of reference for track alignment by tensioning a wire or similar pliable member between two points having a known spatial relationship t0 the aligned track position and then to adjust the position of successive sections of the track to a constant spacing from the reference line. The track adjustment is performed by means of a track lifting and a ballast tamping machine, not itself part of this invention, and measuring means are conventionally provided on the machine to establish the spacing between a section of the track about to be adjusted and a corresponding section of the pliable member. This spacing and its comparison with a desired spacing furnish an indication of the amount of lifting the track section should undergo to reach the aligned position thereof.

The afore-described arrangement has been successful in its application to lengths of track which are desired to extend along a straight line, or in an arcuate path in a horizontal plane since a straight line of reference readily establishes a horizontal plane of reference passing through the line. The arrangement requires relatively complicated modifications if the desired path of the track deviates from a straight line or from a curve in a horizontal plane. Particularly, the proper transition to the superelevation of an outer rail in a curve can be properly determinedrelative to a straight line or ahorizontal plane only by tedious and time consuming comparison with tabulated data, and causes a significant slowing down of operation of the track lifting and ballast tamping machine.

This invention in its basic aspects includes means establishing a reference line vertically above each rail and extending in the direction of elongation of the track to be aligned. The invention further requires measuring means associated with each rail and having a first por tion extending from the rail toward the reference line and a second portion adjacent a point of the line in registry with the afore-mentioned rail. The two portions are coupled by adjusting means responsive to move ment of the measuring means along the track from one track section to a successive one'for varying the spacing between the two portions of the measuring means.

In its more specific aspects, the invention contemplates establishinga reference line by means of an elongated member, such as a wire member, tensioned between a track grading machine and a target fixedly arranged on the length of the track which still requires alignment, it being understood that the track grading machine is positioned on an aligned length of track even though its track lifting and/or ballast tamping devices are positioned to operate on a length of track not yet aligned. A measuring device, for example, a measuring rod, may also be mounted on the track grading machine in such a manner that its lower end portion rests on the track rails whereas its top portion is near the tensioned wires so that the extent of track alignment required may be read from the spacing of the top of the rod from the wire.

To compensate for any sag in the wire, for a desired 3,136,065 Patented June d, 1964 non-linear path of the track, or both, the two portions of the measuring rod are longitudinally movable toward and away from each other, and a cam arrangement is interposed between them to control their spacing, and thereby to control the effective length of the device. The cam arrangement is coupled, to the track grading machine in such a manner that the cam is moved according to the linear travel of the machine along the tracks, and

the length of the rod is adjusted to the desired arcuate shape of the track, to the predictable sag of the wire, or both, by a cam face shaped to take these factors into account.

The desired change in,track level per unit length for the superelevation of rails in curves is known in advance. Cams may readily be prepared in advance for any desired vertical deviation from a straight path, and may further be modified to take the sag of the reference wire into consideration. Practically, the number of interchangeable cams needed for automatic determination of the proper aligned position of a track is relatively small in accordance with established practice which provides for only a limited number of radii of curvature for railroad tracks requiring superelevation.

Other features and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description of a preferred embodiment when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof, and wherein:

FIG. 1 shows a track grading arrangement equipped with the aligning devices of the invention in a fragmentary, side-elevational view; and

FIG. 2 shows elements of the apparatus of FIG. 1 in a front elevational sectional view taken on the line 22.

Referring to the drawing now in detail, there is shown in FIG. 1 the front part of a mobile track grading machine having a frame 1 with a forwardly projecting bracket 1. The frame 1 is supported on at least four wheels of which only one front wheel 2 is visible in FIG. 1. The track grading machine is equipped with track raising and/or shifting devices of a type well known and not shown in order not to crowd the drawing. Such devices have been disclosed, for example in the United States Patent No. 2,734,463 to S. R. Hursh et al. All grading devices mounted on the frame 1 are represented by ballast tamping tools 3 which are also known in themselves and do not require more detailed description. It will be understood that the frame 1 is equipped with two identical sets of grading devices for simultaneous operation on both rails of the track on which the machine travels, as is conventional.

The track essentially consists of two rails 12 connected by a plurality of cross ties 13, and is supported on a roadbed (not shown) topped by a ballast of crushed rock. In the position illustrated in FIG. 1, the wheels 2 of the track grading machine are supported on a previously aligned and graded portion of the track, whereas the overhanging portion of the frame 1 on which the tamping tools 3 are mounted extends over a section of the track which is about to be graded. A target vehicle 4 is mounted at a distance from the track grading machine and is held stationary on the rails 12 of a track section which is not yet aligned by means of clamps 15.

A wire 14 is tensioned between a hook 16 on the vehicle 4 and a guide pulley 5 on the track grader by a tensioning pulley 6. The level of the two end points of the wire 14 on the vehicle 4 and the guide pulley 5 is at a fixed dis.- tance from the proper aligned position of the rails 12. This distance is maintained for the pulley 5 by a rod 29 one end of which is mounted on the journal box of a front wheel 2 whereas the other end carries the guide pulley 5. The rod 20 is vertically slidable on the machine frame 1. The position of the other end of the wire 14 on the hook 16 of the vehicle 4 is selected by surveying methods or in any other convenient manner. In most instances, it will be adequate to make the spacing of the hook 16 from the rail section on which the vehicle 4 is standing equal to the spacing of the top of the pulley 5 from the rail under the wheel 2. The distance of the vehicle 4 from the grading machine will normally be sufficiently great to reduce alignment errors within working range of the grading machine due to vertical misalignment of the rails 12 under the vehicle 4 to negligible amounts.

Constant torque is applied to the tensioning pulley 6 by any convenient known means. In its simplest aspects, the torsion applying means consists of a cylinder coaxial with the pulley 6 and fixedly connected thereto, a rope having one end fastened to the cylinder and wound over its surface in a single-layer helix, and a weight at the free end of the rope. A more elaborate device may consist of a pressure fiuid operated motor, such as a turbine, connected to a source of pressure fluid at constant pressure and having an output shaft which is coupled to the shaft of the tensioning pulley 6. Torque is applied to the pulley 6 in such a direction that the wire 14 is held under tension and the wire is wound on the pulley 6 when the track grading machine moves toward the stationary vehicle 4.

A sheave or grooved pulley 17 is coaxially fastened to the pulley 6 and transmits rotary movement of the latter by means of a belt 18 to another sheave 19 which is coaxially secured to a pinion 7 engaging a rack 21. The several elements transmitting motion from the pulley 6 to the rack 21 have not been drawn to scale. It will be understood that the transmission ratio of the motion transmitting arrangement including the pulley 6 and its constant torque drive, the sheaves 17 and 19, the pinion 7 and the rack 21 is such that the rack will travel its full length engaged with the pinion 7 when the track grading machine travels over the full useful length of the wire 14, that is, from a position in which the wire is fully unwound from the pulley 6 to a position in which the grading machine reaches a terminal position nearest the vehicle 4.

A coupling rod 10 transmits the translatory movement of the rack 21 to the rack 11 of another rack-and-pinion arrangement for rotation of a pinion 27. The pinion 27 is journaled in a housing 22 fixedly fastened on top of a rod 8' which is vertically slidable in the bracket 1'. The bottom end of the rod 8 is forked and is supported on a wheel 8" which travels on the rail 12 just ahead of the track grading machine, that is, on a section of the track which is yet to be aligned and graded. The housing 22 with the rack 11 is free to move up and down relative to the frame 1 as the variations in the level of the rails 12 may require. A shot rod portion 8 is vertically guided in an opening of the housing 22. It is longitudinally aligned with the rod 8 and its lower end is in camming engagement with an eccentric cam disc 9 fastened to the pinion 27 for joint rotation. The cam disc 9 thus rotates when the tensioning pulley 6 turns and the overall length of the structure constituted by the wheel 8", the rod 8', the housing 22 and the rod portion 8, hereinafter referred to as measuring device, varies when the wire 14 is wound on the pulley 6 as the track grading machine moves along the rails 12 toward the vehicle 4.

The wire 14 provides a reference line the end points of which have a fixed spatial relationship to the desired track position. Assuming initially that the apparatus so far described is to be employed for compensating for the sag of the wire 14 between its fixed end points, it will be appreciated that a level track position cannot be laid out by lifting the track to a position having a uniform distance from the sagging wire 14. The measuring device will have to take into account the vertical deviation of the wire along a catenary curve between the top of the guide pulley 5 and the point where measurement actually is being made.

For a given tension applied to the wire by the tensioning pulley 6, a known wire weight per unit length, a known spacing of the pulley 5 from the hook 16, and a known spacing of the measuring device from the pulley 5, this deviation is readily calculated and a cam disc 9 may be constructed accordingly for shortening the measuring device by an amount appropriate for eliminating this source of error. As the grading machine approaches the target vehicle 4, the sag of the wire 14 decreases and the cam disc 9 must be designed in such a manner as to raise the rod portion 8 accordingly. For a constant torque applied to the pulley 6 and a given wire 14, there will be one angular position of the cam 9 coordinated to each distance between the target vehicle 4 and the grading machine. This distance may readily be read from suitable markings on the wire 14 and the cam may be provided with an index mark which is to be aligned with an arcuate scale in the housing 22 which may be calibrated directly in units of distance or free length of the wire 14. Such markings will readily suggest themselves to those skilled in the art and have not been explicitly shown in the drawing. The operator, before making a run with the track grading machine toward a stationary vehicle 4, will thus first set the cam disc 9 into the proper angular position corresponding to the distance between the grading machine and the target vehicle. He will not have to make any other corrections for sag of the wire 14 and be guided in the operation of the machine by the relative position of a mark on the rod portion 8, for example, its top edge, and the Wire 14. It is preferred that the wire 14 rest on the top edge of the rod portion 8 when the track on which the wheel 8 rides is in its proper aligned position, so that the spacing between the top edge and the wire directly indicates the distance by which the rail 12 has to be lifted by the lifting devices (not shown) of the track grading machine.

The operation of the apparatus described is substantially the same when it is desired to bank the track by superelevating one of the rails 12. The track grading machine is equipped with two measuring devices of substantially identical structure, as shown in FIG. 2 which illustrates only the measuring devices of the apparatus of FIG. 1 in a front elevational sectional view on the line 2-2. The cam disc 9 of one of the measuring devices has a cam face which compensates for the sag of the wire 14 only. The other measuring device has a cam disc 9' which additionally shortens the overall length of the measuring device according to a desired superelevation x of the rail, as seen on the left side of FIG. 2. The cam disc 9' is actuated by a rack 11 which is driven by an arrangement identical with that seen in FIG. 1, so that the angular displacement of the cam 9' is uniquely correlated with the movement of the grading machine toward the vehicle and the corresponding shortening of the effective length of the wire 14.

While the method and apparatus of this invention have been described in connection with a specific embodiment, it will be understood that many variations and modifications may suggest themselves to the person having ordinary skill in this art, when benefitting from the present teachings, and Without departing from the spirit and scope of this invention as defined in the appended claims.

This application is a continuation-in-part of our copending application Serial No. 77,329, filed on December 21, 1960, now Patent No. 3,074,174, for apparatus for determining a desired level of a track section to be raised.

What we claim is:

1. In a method of grading an elongated track under the control of respective reference lines extending vertically above respective rails of the track in the direction of their elongation, wherein successive longitudinal sections of said lines are vertically spaced respective distances from the corresponding successive sections of said track rails and wherein measuring means are moved along each of the track rails from one track section to a successive one for measuring the respective distances between said track rail sections and the corresponding sections of said lines, the measured distances controlling the track grading: the step of changing the length of one of said measuring means associated with one of said rails responsive to the movement of said measuring means by a distance substantially equal to the desired superelevation of the one rail.

2. A method for controlling a desired superelevation of one rail of a track section to be raised, comprising:

(a) extending an elongated, flexible tension member along the one rail of the track section and vertically spaced therefrom between two anchor points adjacent respective ends of the track section, said tension member serving as a reference line and determining the lifting stroke parameter for the one track rail;

(b) moving one of said anchor points in relation to the other anchor point as the raising of the track section proceeds;

(c) continuously winding said tension member on a roll under a substantially constant tension during the movement of the one anchor point in relation to the other anchor point;

(at) continuously measuring the vertical distance between the one track rail and the tension member with a longitudinally adjustable vertical measuring element;

(e) continuously changing the length of the measuring element in accordance with the desired superelevation of the one rail; and

(f) controlling the changing of the distance in response to the winding of the tension member on the roll.

3. The method of claim 2, comprising the step of ro- 15 tating a cam synchronously with the rotating roll for changing the length of the measuring element.

References Cited in the file of this patent UNITED STATES PATENTS Talboys Mar. 14, 1961

Claims (1)

1. 2. A METHOD FOR CONTROLLING A DESIRED SUPERELEVATION OF ONE RAIL OF A TRACK SECTION TO BE RAISED, COMPRISING: (A) EXTENDING AN ELONGATED, FLEXIBLE TENSION MEMBER ALONG THE ONE RAIL OF THE TRACK SECTION AND VERTICALLY SPACED THEREFROM BETWEEN TWO ANCHOR POINTS ADJACENT RESPECTIVE ENDS OF THE TRACK SECTION, SAID TENSION MEMBER SERVING AS A REFERENCE LINE AND DETERMINING THE LIFTING STROKE PARAMETER FOR THE ONE TRACK RAIL; (B) MOVING ONE OF SAID ANCHOR POINTS IN RELATION TO THE OTHER ANCHOR POINT AS THE RAISING OF THE TRACK SECTION PROCEEDS; (C) CONTINUOUSLY WINDING SAID TENSION MEMBER ON A ROLL UNDER A SUBSTANTIALLY CONSTANT TENSION DURING THE MOVEMENT OF THE ONE ANCHOR POINT IN RELATION TO THE OTHER ANCHOR POINT; (D) CONTINUOUSLY MEASURING THE VERTICAL DISTANCE BETWEEN THE ONE TRACK RAIL AND THE TENSION MEMBER WITH A LONGITUDINALLY ADJUSTABLE VERTICAL MEASURING ELEMENT; (E) CONTINUOUSLY CHANGING THE LENGTH OF THE MEASURING ELEMENT IN ACCORDANCE WITH THE DESIRED SUPERELEVATION OF THE ONE RAIL; AND (F) CONTROLLING THE CHANGING OF THE DISTANCE IN RESPONSE TO THE WINDING OF THE TENSION MEMBER ON THE ROLL.

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