Abstract:
A railroad track relaying train comprises, in addition to the cars for transporting the ballast screening machines and a car equipped with power-wrenches for fixing the tie-screws, a sequence of working cars including a tie- and rail-removing car, a ballast clearing car, and a tie and rail laying car, these cars being interconnected by means of coupling frames supported by caterpillar trucks adapted to keep the working cars on the selected path. The tie and rail removing car comprises an elevator capable of lifting and rotating at least one tie or a track span around ballast conveyors, in order to deposit at least one tie or track span upon a transport element. The train is capable of performing all of the operations necessary for removing the old track, excavating and screening the old ballast, and laying the new track on the screened ballast, without stopping its forward motion when removing the old track.

Description:
FIELD OF THE INVENTION 
     This invention relates to a railroad track relaying train which, in addition to cars for transporting rails, ties and their fastening means, comprises at least one sequence of working wagons including a track removing car, a ballast-clearing car, a track-laying car, a tie-screw fixing car and means for transporting the old ballast to a screener installed on a wagon outside the track-laying area, together with means for transporting the screened ballast to a storage and dispensing bin, preliminary to its distribution on the new track, and other means for transporting the old ties or track panels or spans and the new ties. 
     Conventionally, a railroad track relaying procedure comprises not only the substitution of new rails and ties for the old ones but also the reclaiming of the ballast, since the old ballast, soiled with dirt and refuse, is clogged and has lost the necessary elasticity and perviousness. On the other hand, the successive additions of gravel during the tie truing and ballast tamping operations are attended by an increment in the track height, and this may prove rather detrimental on railroad sections passing under fixed structures and constructions. 
     DESCRIPTION OF THE PRIOR ART 
     Nowadays, the ballast is normally cleared and screened before or after laying the new track. Therefore, the time necessary for this specific operation adds itself to the time required for performing the other track relaying operations. On the other hand, this ballast clearing and screening operation cannot be accomplished without resorting to powerful means for lifting the complete track, and this step is obviously attended by the risk of altering the shape of the new rails. Now since ballast clearing and screening machines have extremely large dimensions, putting these machines into operation involves time-robbing and complicated maneuvers both when starting and stopping their operation. 
     The Applicants are also the owner of the U.S. Pat. No. 4,004,524 disclosing a method for the complete relaying of a railboard track, wherein the operations consisting in removing the old track, clearing and screening the ballast and laying the new track are accomplished during a single passage of the complete track relaying train provided for this purpose. The same Swiss patent also describes a train for the complete relaying of a railroad track, which comprises not only the cars for transporting the rails, ties and their fixation means, but also at least one sequence of working cars provided with gantries for removing and laying railroad tracks, and frame-cars, such sequence being already known through Swiss Pat. Nos. 549.692 and 585.814 also owned by the Applicants. The equipments of this known track relaying train comprise inter alia means for clearing the ballast and transporting same to a screener mounted on a car located outside the track relaying area. 
     SUMMARY OF THE INVENTION 
     It is the essential purpose of this invention to provide an improved railroad track relaying train whereby all the operations consisting in removing the old ties and rails, and the excavation of the worn ballast, as well as the laying of new ties and new rails, are accomplished without stopping the machine and simultaneously with the removal of the old ties and rails, and in such a way that the train will still better fit within the maximal permissible moving dimensions while increasing the width of the working cars and reducing their wheelbase. 
     These improvements together with other advantageous features to be described presently are obtained by providing on the track removing car a lifting system capable of lifting and turning at least one tie or track panel around at least one of the ballast transport elements, by interconnecting the working cars by means of coupling frames supported by special trucks adapted to travel on the ballast and/or on the cleared track platform or sub-grade, or on the screened ballast, and adapted to be lowered more or less in relation to the relevant coupling frames, so as to raise the bogie-trucks of the working cars in the working area, and finally by the fact that each coupling frame interconnects two adjacent cars through the medium of universal joints and guide members for the purpose of maintaining the position of the working car concerned in relation to the coupling frame. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1 and 2 illustrate diagrammatically the general arrangement of a railroad track relaying train according to this invention. 
     FIG. 3 illustrates the geometrical inscription of the train in a curve. 
     FIG. 4 is a fragmentary side elevational view of a track removing car with its tipping elevator; and 
     FIGS. 5 and 5a are a cross sections of this car and a plane view from above showing the path of the tie movement, respectively. 
     FIG. 6 is another fragmentary side-elevational view showing a modified form of embodiment of the track removing car for removing complete track panels, and 
     FIG. 7 is a detail view showing the coupling between the means transporting the screened ballast and the used or old ballast, respectively; 
     FIG. 8 illustrates in cross-section the movement of the track panel; 
     FIG. 9 is a cross section showing a modified form of embodiment of the track removing car with its rotary elevator for ties; 
     FIG. 10 is a schematic side elevation illustrating the general arrangement of the track relaying train, and 
     FIG. 11 illustrates an embodiment similar to that of FIG. 9 but for track panels. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The railroad track relaying train according to this invention may be constructed for carrying out two different methods of removing the old ties and the old rails: 
     1. A method for removing and loading only the old ties (FIGS. 4, 5 and 9). The old rails 1 are spread apart and laid behind the machine either on the shoulder of the bedding or along the track axis. They are discharged at the end of the relaying operations. 
     2. A method for removing complete track panels or spans with the assistance of a rotary elevator 26 adapted to lift and turn the track panels upside down and to lay them upon lorries 41 rolling on a transport runway or level 40 so as to be eventually discharged by means of gantries (FIGS. 6 and 8). 
     The railroad track relaying train comprises six main component elements shown diagrammatically in FIGS. 1, 2 and 10, namely a screener (not shown), a track removing car 5, a ballast-clearing machine 6, a track-laying car 7, a tie-screw fitting car 46 followed by transporting cars 47 and gantries 48 and 49 equipped with a transport beam (not shown). 
     The ballast screening machine and the tie-screw fitting car, not described herein are conventional two-bogie-truck cars. The track removing car 5, the ballast-clearing car 6 and the track-laying car 7 constitutes together a hinged sequence of wagons supported by six bogie-trucks 12 to 17 and by two caterpillar or creeper-mounted trucks 11 and 11&#39;. 
     During the track relaying operations, the screener and the first bogie-truck 12 of the track removing car 5 run on the former track 1. The central section of the train bears on the pair of caterpillar or creeper trucks 11 and 11&#39; rolling the leading one of the ballast and the trailing one of the excavated track platform, or on the screened ballast. The rear bogie-truck 17 of the track laying car 7 as well as the tie-screw fitting car run on the new track 4. 
     Also during the operations the two caterpillar trucks 11 and 11&#39; and the tie-laying machine are either guided under the control of feelers utilizing the parallel adjacent track for this purpose, or driven with the assistance of a measuring and control system mounted on the screener, the track-removing car, the ballast-clearing machine and the track-laying car, respectively, as illustrated diagrammatically in FIG. 3. The geometrical points A, B, C, D, E, F and b, c, d, e are also shown in FIG. 1. 
     The working wagons (5, 6 and 7) are interconnected by coupling frames (8, 8&#39;) supported by the caterpillar trucks (11, 11&#39;). Each coupling frame 8, 8&#39; interconnects two adjacent wagons by means of universal joints 9. Guide members 10 are provided for keeping the chassis of the car concerned in the proper transverse position in relation to the coupling frame 8, and hydraulic bumpers 42 are also provided for guiding the relevant coupling frame in a predetermined longitudinal position with respect to the wagon chassis. 
     The two caterpillar trucks 11, 11&#39; are mounted on turntables. Hydraulic cylinders are provided for lowering, lifting and guiding these trucks 11, 11&#39;. Adequate hydrostatic drive means provide a variable working speed. The caterpillar trucks may be guided in three different ways: 
     by using feelers mounted on the caterpillar trucks and utilizing the parallel adjacent track as a reference, or 
     by using a device responsive to the position of the former track 1 measured by means of rail feelers mounted on the screener ahead of the working area, and also by resorting to a method of measuring angles (α, β, γ, δ) between the coupling frames 8, 8&#39; and the adjacent working cars (FIG. 3), or 
     by using manual control means. 
     Automatic control means are also provided so that the two caterpillar trucks follow the trace of the former track or a trace parallel thereto when it is desired to change the distance between parallel tracks. 
     The track removing car 5 (FIGS. 1 and 4) is supported at the front by a bogie-truck 12 and at the rear through the intermediary of a hinged frame 8 supported in turn by the relevant caterpillar truck 11. Mounted on the car are the conveyors 18 for the excavated material and the overhead conveyors 19 for the reclaimed ballast. The old ties are removed and transported by using a hydraulic excavator or digger 20, endless-chain conveyors 21 and an elevator 22. 
     Behind the bogie-truck 12, roller-type rail-jacks (not shown) are provided for lifting and spreading apart the old rails 1 which are subsequently transferred along the machine and eventually laid at the rear upon the track sub-grade or platform or along the track axis. 
     In the exemplary form of embodiment illustrated in FIGS. 4 and 5, the hydraulic excavator or digger 20 extracts the old ties 32 one by one from the ballast and lays them down upon an endless chain conveyor 21 directing the old ties onto a storage conveyor 21&#39;. The elevator 22 comprises a pivoting arm 36 and a rotary clamping head 37 and is adapted to pick up three ties 32 at a time from the storage conveyor 21&#39;, lift and pivot these ties backwards by means of the pivoting arm 36, thus causing them to rotate through 90 degrees in the track plane with the rotary clamping head 37. Then the elevator 22 lifts the turned ties 33 laterally of the old-ballast conveyor 18, above the level of the tie conveyor 23. The ties are subsequently pivoted and rotated forwards still in the plane of the underlaying track, and finally laid upon the conveyor 23 which transfers them to the transport gantries. The elevator is then returned through the same path to its initial position. 
     All the movements of the working cycle may be controlled automatically or manually. 
     Alternatively, the track removing car may be equipped with an elevator 22 arranged for lifting and pivoting the ties in the track plane around both conveyors 18 for the old ballast and 19 for the screened ballast, respectively. 
     In another form of embodiment of the invention illustrated in FIG. 9, the rotary elevator 43 provided with hydraulic claws 44 mounted on a lifting system is adapted to grip three ties at a time from the storage conveyor and to lift them against the elevator. The latter turns the ties around the old ballast conveyor 18 and screened ballast conveyor 19, and eventually deposits the ties upside down upon the top level from which they are picked up by the movable conveyor 45 and transferred to the gantries. Then, the elevator 43 resumes its initial position. All the movements of the cycle are controlled automatically or manually. 
     Alternatively, the tie removing car may be provided with an elevator 43 adapted to turn the ties only around the old ballast conveyor 18 as in the case illustrated in FIG. 5, but in this modified version the ties are disposed upside down on the conveyor 45. 
     In another specific form of embodiment contemplated in the present invention for removing complete track panels or spans 35, as illustrated in FIGS. 6 and 8, the track removing car 5 comprises a central girder 24 in which the conveyor 18 for the excavated material is housed, the conveyor 19 for the reclaimed ballast being located overhead. A rotary elevator 26 equipped with hoisting means and a runway 40 for the lorries 41 is suspended by means of rollers 27 from the central girder 24. The hoisting means comprises two pairs of rolling claws 28 secured to hinged frames 29, with hydraulic cylinders for lifting and moving said claws laterally. The track panels are disposed upside down on the lorries 41 rolling on runway 40. 
     In a modified version of this embodiment according to FIG. 11, the track removing car may be equipped with a rotary elevator 43&#39; similar to FIG. 9, adapted to lift and rotate the track panels 35 by means of rolling claws 28 secured to hinged frames 29 (as in FIG. 8) both around the old ballast conveyor 18 and around the screened ballast conveyor so that the track panels are disposed upside down on lorries rolling on runway 40&#39; above convey 19. 
     The track panels may be removed without discontinuing the operation of the machine. During the picking up of the next track panel, the one stored on the ballast-clearing machine is moved forwards by another train of lorries until it reaches the laying car 7 where it is taken over by the gantries 48, 49 (FIG. 10) and transported on loading wagons. 
     The ballast clearing car or machine 6 (FIG. 1) comprises a pair of bogie-trucks 14, 15, an excavator 30, a ballast metering unit and means for transporting the ballast, the track ties or the track spans or panels. This car 6 is coupled at its leading end to the track removing car 5 and at its trailing end to the track-laying car 7, both couplings occuring through a hinged connecting frame 8, 8&#39; supported by a caterpillar truck 11, 11&#39;. During the track relaying operations, the track clearing machine is supported by the pair of caterpillar trucks 11 and 11&#39; running on the old ballast and the excavated truck platform, or on the screened ballast. 
     The excavator 30 comprises an excavating chain and an equalizing or levelling blade 25. The excavator is pivotally mounted on the frame and suspended by means of hydraulic cylinders so that the working depth and inclination of the platform can be adjusted at will. The blade is provided with side plates adjustable during the operation of the machine by means of hydraulic cylinders. Behind the levelling blade 25 a tamper is provided for compacting the track platform. 
     The material dug by the excavator is delivered by the excavating chains to conveyors 18 and thus directed towards the screener. The reclaimed and screened ballast is then directed by conveyors 19 to the rear end of the train and fed to the reclaimed-ballast metering device comprising a fixed bin and a metering element adjustable in the vertical direction as a function of the requisite thickness of the ballast layer. From the storage bin, the ballast is fed to the metering device to provide the first ballast layer and the excess ballast is delivered to an intermediate conveyor and thus fed to the ballast distributor mounted on the track laying car. Behind the ballast metering device a tamper is also provided for compacting the ballast before laying the ties. 
     The relatively long transport path followed by the old ballast and by the screened ballast along the train may become an inconvenience when the train is stopped for any reason during its operation. It would be necessary to stop all the conveyors carrying excavated and screened material for preventing an unequal distribution of the ballast beneath the laying car. Now starting all the loaded conveyors simultaneously would constitute a heavy demand of electric power and might delay the resumption of normal operations. To avoid these drawbacks, the present invention provides a transport connection established at will but preferably automatic each time the train is stopped. To this end, a hopper 31 located as close as possible to the excavating chain is disposed between the transport chains 18 for the old ballast and 19 for the screened ballast. The transport connection, creating a closed-circuit condition between the screened ballast and the used ballast, is obtained by shifting the screened ballast conveyor 19&#39; with the assistance of a hydraulic cylinder 39 when the machine is stopped. 
     The track laying car 7 provided with two bogie-trucks 16 and 17 is equipped with tie-laying means, together with the conveyor elements, the rail laying members and the ballast distributor. During operation, the car 7 is caused to bear at its front end on the caterpillar-mounted connecting frame 8&#39; and at its rear end on the bogie-truck 17 rolling on the new track 4. Also mounted on the rear portion of the car 7 are the new rails laying members comprising, inter alia, roller claws clamps or nippers. 
     The new ties 52 stored on transport wagons 47 are transferred by means of gantries 48, 49 to a storage conveyor 51 of the car 46 equipped with the tie-screw fitting means. An intermediate conveyor separates the ties and feeds them to rotary clamps disposed at the rear end of the track laying car 7. These clamps lift and turn two ties at a time, and lay them upon a longitudinal conveyor divided into several sections for the intermediate storage. The ties 52 are thus transferred by the longitudinal conveyor to the tie-laying machine where they are centered, positioned and finally laid upon the ballast, as shown schematically by arrow 53 in FIG. 10. 
     The relative spacing of the ties thus laid down is set by means of a measuring device adapted to change this spacing centimeter by centimeter. The ties are also positioned in the transverse direction either by means of a feeler controlling the distance between the tie axis and the parallel track or by means of a measuring system associated with adequate control means provided on the working car. 
     The tie-screw fitting car 46 (FIG. 10) comprises power-wrenches for fastening the new rails by means of tie-screws. Moreover, this car 46 is used for transporting the gantries 48 and 49. The dimensions of this car 46 are such that crew can fit the tie fastening means from inside the car. 
     The pair of self-propelled gantries 48 and 49 is constructed according to the teachings of Swiss Pat. No. 549.692, for transporting the old and new ties to and from the working cars and the transport cars 47. These two gantries 48, 49 are interconnected by a central girder from which a tie transporting beam is suspended by means of ropes and hydraulic cylinders. It also comprises hydraulically actuated claws for gripping the ties or the track spans. 
     The complete relaying of a railroad train according to the instant invention comprises the following operations: 
     I--Removing the old ties and rails. 
     Variant Ia: 
     Removing the rail fixing means in front of the machine; 
     Spreading the old rails apart, behind the front bogie-truck of the rail removing car, with the assistance of rolling claws; 
     Extracting the old ties by using the hydraulic excavator and transferring them through the chain conveyors and an elevator to the storage conveyor at the laying car. 
     Variant Ib: 
     Removing the old track panels or spans by means of the rotary elevator, then laying them upon the lorries and transporting them in two successive runs to the laying car. 
     II--Excavating the ballast, equalizing and compacting the track sub-grade or platform; 
     III--Screening the ballast by using a vibrating screen and a rotary screen; the reclaimed ballast is transported to the metering device behind the excavation chain and to the ballast distributor at the rear end of the track laying car; any refuse is either deposited laterally of the track platform or loaded into a special car; 
     IV--Laying the new ties by using the tie laying apparatus; 
     V--Laying the new rails on the ties by using rotary claws in front of the rear bogie-truck of the track-laying car; 
     VI--Transporting the old ties or, as the case may be, the old track spans or panels, by using the gantries equipping the transport car and supplying new ties by using the gantries from the transport car to the laying car; 
     VII--Fixing the rails by using the tie-screw fastening means contemplated.