US20030010571A1 - Method and apparatus for lubricating railroad tracks - Google Patents
Method and apparatus for lubricating railroad tracks Download PDFInfo
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- US20030010571A1 US20030010571A1 US10/238,451 US23845102A US2003010571A1 US 20030010571 A1 US20030010571 A1 US 20030010571A1 US 23845102 A US23845102 A US 23845102A US 2003010571 A1 US2003010571 A1 US 2003010571A1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61K—AUXILIARY EQUIPMENT SPECIALLY ADAPTED FOR RAILWAYS, NOT OTHERWISE PROVIDED FOR
- B61K3/00—Wetting or lubricating rails or wheel flanges
Definitions
- the present invention relates to the lubrication of railroad tracks and, in particular, to an improved method of controlling the amount of lubricant applied to the tracks of a switchyard.
- the cars of a train are disassembled and reassembled into new trains in a yard that has numerous parallel tracks that are accessible from the opposing ends thereof by access tracks connected by switches.
- the track including curves and switches, are currently lubricated by injecting a lubricant through outlets on to the surface of the tracks.
- the cars of an incoming train are disassembled and recombined with cars from other incoming trains into a plurality of new outgoing trains, with the cars of each new train lined up on a separate track in the yard.
- One method is a hump yard for such purposes, where a switch engine moves a car over a hump at a speed of approximately three miles per hour.
- the cars are independently released on the crest of the hump and allowed to roll down the far side of the hump and across switches to tracks on which the new trains are being formed.
- the speed of the car as it moves along the track system is controlled by a series of retarders.
- a computer associated with each retarder receives information regarding the weight of the incoming car and has a sensor for determining the speed at which the car is entering the retarder. It also maintains as count of the number of cars being directed to each yard track and adjusts the application of the retarder based on the incoming speed, the weight of the approaching car and the space remaining on the yard track.
- Other sensors in the system follow the car's progress across the switches of this system and prohibit the premature throwing a switch along the path of a rolling railroad car. Except for weight, the retarders of a hump yard system are not responsive to the condition of an individual car or to the condition of the track.
- the dispensers now being used to lubricate the tracks of a yard system have an associated detector for detecting that a car is approaching and the dispenser dispenses a fixed amount of lubricant each time a car passes.
- a railroad car that does not have its brake applied and is free of defects will move along the tracks of the system at a predictable rate.
- Over lubrication will cause excess lubricant to build up in the yard tracks.
- Excess lubricant is a hazard to railroad personnel, can cause roll out, can cause damage to the cars and the contents thereof, and contaminates the underlying ground.
- Lubricant that is dispensed on a track is picked up by the wheels of a moving railroad car and spread down track. Once a few cars have applied lubricant to a previously underlubricated track, the cars will again begin moving at their desired speeds, after which only intermittent application of lubricant are needed to maintain adequate lubrication. It is unnecessary, therefor to apply lubricant to the tracks each time a car is released over a hump as currently done in a hump yard.
- the present invention is embodied in a method of controlling the application of lubricant to the tracks of yard rail systems of the type having an access track leading to a plurality of switches and then into a second plurality of yard tracks into which moving railway cars can be directed.
- a primary lubricating station is provided immediately following the primary retarders. Where the yard has a hump, the primary retarder is positioned immediately after the hump.
- a speed detector detects the presence and the speed of a railroad car approaching the primary lubricating station. Secondary lubricating stations may be provided down track to lubricate the yard tracks as needed.
- Each lubricating station has a reservoir of lubricant, a positive displacement pump, and a plurality of nozzles arranged to apply lubricant along a portion of rail having a length approximately equal to the circumference of a wheel of a railroad car.
- a positive displacement pump Positioned down track, along each of the yard tracks of the system, are detectors for detecting when a rail car has passed.
- a logic which may be a computer, receives input from the speed detector and the down track detectors and calculates the speed of the car as it moves through the tracks by dividing the length of track between the primary lubricating station and the down track detector by the time needed to pass between the two points. The calculated average speed of the car is then compared to a predetermined desired speed retained in the memory of the computer. The difference between the desired speed and the actual car speed is used by the logic to control the rate at which lubricant is applied to the tracks. When the logic determines that cars are losing speed more rapidly than desired, the logic will cause the pump and the nozzles to dispense lubricant immediately before the next railroad car reaches the station. On the other hand, were the logic to determine that the speed of cars down track equals the desired speed, the amount of lubricant being dispensed on the tracks will be reduced or terminated.
- FIG. 1 is a schematic view of the tracks of a yard rail system
- FIG. 2 is a top view of the nozzles of a dispensing system for dispensing lubricant positioned on a track in the yard system shown in FIG. 1;
- FIG. 3 is a schematic side view of the nozzles and dispensing system shown in FIG. 2 with the wheel of a railroad car rolling thereon.
- FIG. 4 is a schematic diagram of the feedback system for controlling the dispensing of lubricant through the nozzles shown in FIG. 2, and
- FIG. 5 is a schematic view of a lubricating system for the switch plate of a switch.
- a typical yard track system 10 has a hump 12 , across which is a feeder track 14 .
- Feeder track 14 passes a first retarder 16 after which there is a first switch 18 for dividing the track 14 into two tracks 19 , 20 .
- first switch 18 Following the first switch 18 are secondary switches 21 , 22 , 23 , and following the secondary switches 21 , 22 , 23 are secondary retarders, not shown.
- secondary retarders Following the secondary retarders are further switches 32 , 34 which ultimately breaks the lines down to yard tracks 36 , 37 , 38 , 39 , 40 , 41 , 42 .
- At the far end of the yard are a second plurality of switches 44 - 44 leading to an exit lead 46 across which the assembled trains are withdrawn.
- An incoming train is broken up by releasing cars over the hump 12 and allowing them to roll down the feeder track 14 and into the yard tracks 36 - 42 .
- the retarder 16 has a computer, not shown, which receives input from a speed detector, not shown, and from a scale, not shown, which categorizes the weight of the car. Using these two pieces of information and a look up table stored in its memory, the computer adjusts the resistant force applied by the retarder 16 to the wheels of the car. If a railroad car is not defective the car will be moving a the optimum speed when it leaves the retarder and it will move at a predictable speed down track to its destination provided the track has been properly lubricated.
- a defective car that is one having the brake applied when it shouldn't be applied, or having worn wheel bearings, will leave the retarder at a significantly slower speed than the optimum speed and the noticeably slow moving car can be detected and identified by the first sensor 64 .
- a defective car will also move through the system at a noticeably slower rate of speed. Defective cars are therefor identifiable by their reduced speed after leaving the retarder.
- a lubricating station 50 located behind the first retarder 16 on the feeder track 14 is a lubricating station 50 .
- the lubricating station 50 has a supply tank 52 , a positive displacement pump 54 for ejecting the lubricant in the supply tank 52 , a motor 56 for operating the pump 54 , and a network of feeder lines 58 for directing lubricant to a plurality of nozzles 60 - 60 .
- a microprocessor 62 controls the operation of the motor 56 and thereby regulates the discharging of lubricant through the nozzles 60 - 60 .
- the micro processor 62 receives input form a first sensor 64 which detects the speed of a car approaching the lubricating station 50 and from a plurality of secondary detectors 65 , 66 , 67 , 68 , 69 , 70 , 71 , each of which is positioned on one of the yard tracks 36 , 37 , 38 , 39 , 40 , 41 , 42 respectively.
- the dispensing system includes two mounting bars 72 , one positioned along the inner surface of each of the rails of a track 74 . Positioned along the length of each of the mounting bar 72 are the nozzles 60 - 60 which are of a type known in the art for dispensing lubricants.
- Each mounting bar 72 has a length 73 which is approximately equal to the circumference of a typical rail car wheel 75 so that lubricant dispensed through the nozzle 60 - 60 on the mounting bar 72 will lubricate the entire circumference of the wheel 75 as it rolls across the lubricated portion of track 74 .
- the wheels of the railroad car will then transport the lubricant down the feeder track 14 to the selected yard track into which the car is directed.
- the invention requires that the nozzles 60 - 60 be positioned sufficiently close to one another and that the pump 54 eject an adequate amount of lubricant on each application to apply a continuous path of lubricant along the entire length 73 of the track 74 .
- the viscosity and other properties of the lubricant changes with temperature, and that the amount of lubricant being applied by the nozzles 60 - 60 is not constant unless the pump 54 is a positive displacement pump.
- the pump 54 is a positive displacement pump.
- each nozzle 60 has an associated valve 76 .
- the valves 76 - 76 are sequenced, such that each valve 76 is successively independently opened. All the lubricant dispensed by the pump 54 will then pass through only none nozzle at a time thereby insuring that the nozzle 60 - 60 all dispense an equal amount of lubricant.
- FIGS. 1 and 4 As a moving railroad car reaches the associated yard track 36 , 37 , 38 , 39 , 40 , 41 , 42 , it will pass over the associated detector 65 , 66 , 67 , 68 , 69 , 70 , 71 , which will send a signal to the microprocessor 62 designating the arrival time of the car.
- the microprocessor 62 includes a clock 77 and a memory 78 , and the microprocessor 62 will divide the time that has elapsed from when the car crossed the first detector 64 to when it arrived at the secondary detector by the distance traveled to calculate an average speed for the car.
- the microprocessor 62 will direct power to the motor 56 for operating the pump 54 and apply lubricant to the track when the wheels 75 of the next railroad car approaches the station 50 . If the microprocessor 62 determines that the cars are rolling at the desired speed, it will not direct power to the motor 56 when the next railroad car approaches thereby controlling the further lubrication of the tracks.
- the microprocessor 62 is also responsive to a rain detector 79 that detects when the tracks in the system are being lubricated by rain or snow. It is not necessary to lubricate wet tracks because water is an adequate lubricant. Accordingly the computer 62 is programmed to ignore readings from the detectors while the rain detector indicates the tracks are wet. The rain may, however, wash lubricant off the tracks, and therefore the computer 62 will initiate new calculations to determine track lubrication as soon as the tracks dry. The micro processor 62 will therefor energize the motor 56 on information detected after the tracks have dried that show that cars are moving below the desired speeds. The microprocessor will also detect the presence of a potentially defective railroad car and notify the central office 88 as is further described below.
- the invention further includes secondary lubrication stations 80 , 82 , 84 positioned after switches 18 , 21 and 22 and prior to switches 23 , 32 and 34 .
- Each of the secondary lubrication stations 80 , 82 , 84 has a supply tank, a motor, a positive displacement pump, nozzles and a microprocessor (all not shown) as described with respect to the primary lubrication station 50 , and has a detector 81 , 83 , 85 respectively, associated therewith.
- the detectors 81 , 83 , 85 of the secondary stations 80 , 82 , 84 are positioned immediately before the associated secondary station and signal the station when a railroad car is approaching.
- Each secondary lubrication station 80 , 82 , 84 receives additional input only from the detectors which are located down track of the station. That is, station 80 receives input only from detectors 65 , 66 , station 82 receives input only from detectors 67 , 68 , and station 84 receives input only from detectors 70 , 71 .
- the secondary stations 80 , 82 , 84 provide lubrication to only a portion of the track system 10 and not to the entire system as does the primary station 50 , and are activated only after the computer 62 of the primary lubricating station 50 determines that the access tracks are already adequately lubricated. For example, if a number of cars have been directed down tracks 14 and 19 to yard tracks 65 and 66 , the entire length of this portion of the system will have become lubricated as a result of the lubricant dispensed from the primary station 50 . The cars directed to yard tracks 65 and 66 would then be rolling at the desired average speed and the station 50 would not be applying lubricant to the tracks.
- the microprocessor 62 of the primary station 50 will not direct power to the motor 56 to further lubricate the tracks.
- the microprocessor of the secondary station 82 will measure the time required for a car to pass from the detector 83 associated with the station 82 to the down track detectors 67 and 68 . If this microprossor determines that these cars are not moving at the desired speed, it will direct power to the associated motor and the secondary station 82 will commence lubricating the tracks prior to the passing of each railroad car. The secondary station will continue to dispense lubricant to the tracks until the cars are again rolling at the desired speed, after which the secondary station 82 will stop lubricating the tracks prior to the passage of a railroad car.
- the present invention provides feedback from down track of the speed of the railroad car. Where the speed of the car is below a predetermined speed, the lubricating stations 50 , 80 , 82 , 84 will dispense lubricant on the track 74 immediately before the arrival of the next railroad car. The rolling cars will pick up the lubricant on the wheels thereof and apply it to the track as they move. The system will continue to dispense a fixed amount of lubricant on the tracks prior to the passing of a railroad car until the microprocessors 62 of the various stations determine that the cars are rolling at speeds consistent with lubricated tracks, after which the microprocessors 62 will terminate the dispensing of lubricant.
- a feature of the present invention is that it will identify potentially defective cars. It is far more expensive to deal with a defective car after it has been incorporated into a moving train than to repair the car while it is still in a yard.
- the microprocessor 62 of the various stations 50 , 80 , 82 , 84 will identify the car as defective and will not energize the associated motor 56 to eject lubricant on the tracks in the path of the car.
- the microprocessor 62 will also ignore all information from the various sensors triggered by the car in determining whether lubrication is needed for succeeding cars thereby avoiding erroneous information into its calculations.
- the microprocessor will notify the central office 88 of an exceptionally slowly moving car that may be defective.
- the invention further includes a lubrication station 90 positioned at each switch 18 , 21 , 22 , 23 , 32 , 34 of which switch 18 is exemplary of all such switches.
- a switch 18 includes a pair of non-parallel lengths of track having moveable end portions the distal ends of which are the switch points 106 , 108 .
- a switch normally has a first switch point 106 contacting the track to which it is adjacent and a second switch point 108 spaced from the track to which it is adjacent, and when the switch is thrown the switch points move until the first switch point is spaced from its adjacent track and the second switch point in contacting its adjacent track.
- the switch 18 has an electric motor 91 and a drive system, not shown, that moves a plurality of slideable switch plates, all of which are identified generally at 96 .
- a drive system not shown
- the switch plates 96 When the switch plates 96 are not lubricated they rapidly become worn and require replacement.
- the motor 91 When the switch plates 96 are unlubricated the motor 91 will also draw a significantly greater amount of electric power to operate the switch than when it is lubricated.
- the switch points 106 , 108 become worn for different reasons than do the switch plates 96 .
- the frequent operation of the switch 18 will cause rapid wear to unlubricated switch plates 96 without causing a similar amount of wear to the switch points 106 , 108 .
- the movements of hundreds of cars across the unlubricated switch points 106 , 108 of a switch which is rarely operated will cause wear to the switch points 106 , 108 without causing a corresponding amount of wear to the switch plates 96 .
- the switch plates 96 and the switch points 106 , 108 of a railroad system are therefore subject to wear which may require costly repairs.
- the lubrication station 90 includes a reservoir, a positive displacement pump, and a motor (not motor 91 of the switch), none of which are shown, similar to those discussed with respect to the primary lubrication station 50 .
- the lubrication station 90 also includes a means 98 for detecting the amount of current drawn by the motor 91 as it begins to move the switch plates 96 .
- the current being drawn by the motor 91 may be measured directly by means of an ammeter or the like, or indirectly by measuring the magnetic field that builds up around the power cable to the motor 91 .
- the amount of current being drawn by the motor 91 is indicative of the amount of lubrication of the switch plates 96 , the motor 91 requiring significantly more power to operate unlubricated switch plates than lubricated switch plates.
- the station 90 further includes a microprocessor 99 having a memory and stored in the memory is the maximum allowable amount of power that the motor 91 is permitted to draw.
- the microprocessor determines that the power detected by means 98 exceeds the threshold maximum stored in the memory of the microprocessor 99 (exceeding the threshold being indicative of unlubricated switch plates) the microprocessor 99 will direct power to the motor of the system 90 to send lubricant through the primary nozzles 100 and lubricate the switch plates 96 .
- the microprocessor 99 can detect that the motor 91 is drawing an excessive amount of power and the motor and pump of the station 90 can direct lubricant to the switch plates 96 before the motor 91 causes movement of the switch plates 96 .
- the switch points 106 , 108 and switch plates 96 wear differently and the fact that the switch plates 96 are unlubricated is a poor indicator of the condition of the switch points 106 , 108 .
- the microprocessor 99 may also energize the motors and pumps to discharge lubricant through the secondary nozzles 102 , 104 to lubricate the switch points 106 , 108 .
- the secondary nozzles 102 , 104 are positioned to direct a flow of lubricant at a point on top of the track that precedes the switch points 106 , 108 by a distance approximately equal to the circumference of the wheel of a railroad car.
- the lubricant When lubricant is dispensed to the top of a track, the lubricant will be picked up on the wheels of the next passing railroad car. Where the lubricating point precedes the switch point by approximately the circumference of a wheel, the wheels of the next passing railroad car will go through one revolution after which they will transfer some of the lubricant thereon to the surface of the switch point thereby lubricating the switch point.
- the microprocessor 99 has been described as responding to a signal from a means 98 for detecting the amount of current drawn by the motor 91 , the microprocessor 99 could also be programmed to initiate an application of lubricant each time the switch is thrown without regard to the amount of power drawn by the motor 91 .
- a pair of detectors 92 , 94 positioned on opposite sides of one of the switch plates 96 would be suitable to signal the microprocessor 99 that the switch 18 has been thrown.
- Lubricating the switch plates each time the switch is thrown may be suitable for an infrequently used switch, but it may lead to over lubrication of a frequently used switch.
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Abstract
The tracks of a railroad yard system have an access track and a plurality of switches leading to a plurality of yard tracks are lubricated by a lubricating station positioned on the access track. In addition to lubricating the tracks, lubrication nozzles are directed at the switch plates and switch points of the switches of the system. Detectors are positioned on the yard tracks to determine the speed of the cars as they roll down track and into the yard, and a computer, responsive to these detectors, control the discharge of lubricant by the lubricating station. Detectors are also positioned near each switch plate to detect when each switch plate moves, and a dispensing system dispense lubricant through the nozzle directed toward a switch plate whenever the switch plate is moved.
Description
- This is a continuation in part of our co-pending application filed Aug. 7, 2000 and assigned Ser. No. 09/633,390. The present invention relates to the lubrication of railroad tracks and, in particular, to an improved method of controlling the amount of lubricant applied to the tracks of a switchyard.
- It is well known that the application of a lubricant to the surfaces of railroad tracks improve the rollability of railroad cars thereby significantly reducing the rate at which the tracks become worn by the wheels of the cars which move along them. Lubricating the tracks also reduces the wear to the wheels of the cars. Curves and switches are particularly subject to wear.
- The cars of a train are disassembled and reassembled into new trains in a yard that has numerous parallel tracks that are accessible from the opposing ends thereof by access tracks connected by switches. The track, including curves and switches, are currently lubricated by injecting a lubricant through outlets on to the surface of the tracks.
- Within the yard the cars of an incoming train are disassembled and recombined with cars from other incoming trains into a plurality of new outgoing trains, with the cars of each new train lined up on a separate track in the yard. One method is a hump yard for such purposes, where a switch engine moves a car over a hump at a speed of approximately three miles per hour. The cars are independently released on the crest of the hump and allowed to roll down the far side of the hump and across switches to tracks on which the new trains are being formed.
- In a hump yard, the speed of the car as it moves along the track system is controlled by a series of retarders. A computer associated with each retarder receives information regarding the weight of the incoming car and has a sensor for determining the speed at which the car is entering the retarder. It also maintains as count of the number of cars being directed to each yard track and adjusts the application of the retarder based on the incoming speed, the weight of the approaching car and the space remaining on the yard track. Other sensors in the system follow the car's progress across the switches of this system and prohibit the premature throwing a switch along the path of a rolling railroad car. Except for weight, the retarders of a hump yard system are not responsive to the condition of an individual car or to the condition of the track.
- The dispensers now being used to lubricate the tracks of a yard system have an associated detector for detecting that a car is approaching and the dispenser dispenses a fixed amount of lubricant each time a car passes. When the tracks are properly lubricated, a railroad car that does not have its brake applied and is free of defects will move along the tracks of the system at a predictable rate. In reality, however, several factors affect the amount of lubricant needed to maintain the optimum rollability of cars aver the tracks. Over lubrication will cause excess lubricant to build up in the yard tracks. Excess lubricant is a hazard to railroad personnel, can cause roll out, can cause damage to the cars and the contents thereof, and contaminates the underlying ground.
- Water is a natural lubricant and, therefore, a lesser amount of lubricate is needed on the tracks during rain or snow. On the other hand, rain or snow will wash some of the lubricant off the tracks leaving the tracks in need of restoration of the desired level of lubrication after the rain has ended. Cars moving along the tracks of an adequately lubricated yard system will lose speed at a predictable rate thereby allowing the orderly assembly of the cars on the yard tracks. On the other hand, the cars move more slowly along inadequately lubricated tracks, as occurs following a rainstorm.
- Lubricant that is dispensed on a track is picked up by the wheels of a moving railroad car and spread down track. Once a few cars have applied lubricant to a previously underlubricated track, the cars will again begin moving at their desired speeds, after which only intermittent application of lubricant are needed to maintain adequate lubrication. It is unnecessary, therefor to apply lubricant to the tracks each time a car is released over a hump as currently done in a hump yard.
- All of the foregoing problems could be reduced or eliminated by providing a means of measuring the need for lubricant on the tracks of a yard system and controlling the application of lubricant in response to the measured need. Until the present invention, the railroad industry has not had such a means for measuring the need for lubricant on the tracks of a yard system.
- Briefly, the present invention is embodied in a method of controlling the application of lubricant to the tracks of yard rail systems of the type having an access track leading to a plurality of switches and then into a second plurality of yard tracks into which moving railway cars can be directed. In accordance with the invention, a primary lubricating station is provided immediately following the primary retarders. Where the yard has a hump, the primary retarder is positioned immediately after the hump. A speed detector detects the presence and the speed of a railroad car approaching the primary lubricating station. Secondary lubricating stations may be provided down track to lubricate the yard tracks as needed. Each lubricating station has a reservoir of lubricant, a positive displacement pump, and a plurality of nozzles arranged to apply lubricant along a portion of rail having a length approximately equal to the circumference of a wheel of a railroad car. Positioned down track, along each of the yard tracks of the system, are detectors for detecting when a rail car has passed.
- A logic, which may be a computer, receives input from the speed detector and the down track detectors and calculates the speed of the car as it moves through the tracks by dividing the length of track between the primary lubricating station and the down track detector by the time needed to pass between the two points. The calculated average speed of the car is then compared to a predetermined desired speed retained in the memory of the computer. The difference between the desired speed and the actual car speed is used by the logic to control the rate at which lubricant is applied to the tracks. When the logic determines that cars are losing speed more rapidly than desired, the logic will cause the pump and the nozzles to dispense lubricant immediately before the next railroad car reaches the station. On the other hand, were the logic to determine that the speed of cars down track equals the desired speed, the amount of lubricant being dispensed on the tracks will be reduced or terminated.
- Occasionally a car will move along the tracks of a system at an excessively high rate of speed or at an exceptionally low rate of speed. A car will move at an excessively high rate if the retarder does not function properly or has failed altogether. A car will move at an exceptionally slow rate of speed if the brake on the car is being applied or if the car is defective in some manor. In accordance with the invention excessive speeds or exceptionally low speeds are detected by a speed detector located before the primary lubrication station. When the logic determines that the initial speed of the car does not fall within expected perameters the system will not apply lubricant to the tracks ahead of the car and the speed of the car will be ignored for determining the need for further lubrication of the tracks. Also, the system will identify an exceptionally slow moving car so that the car can be checked before it leaves the yard. It is far more expensive to deal with a defective car on the open track than in a yard where repairs can easily be made.
- A better and more complete understanding of the current invention will be had following reading the following detailed descriptions taken in conjunction with the drawings wherein:
- FIG. 1 is a schematic view of the tracks of a yard rail system;
- FIG. 2 is a top view of the nozzles of a dispensing system for dispensing lubricant positioned on a track in the yard system shown in FIG. 1;
- FIG. 3 is a schematic side view of the nozzles and dispensing system shown in FIG. 2 with the wheel of a railroad car rolling thereon.
- FIG. 4 is a schematic diagram of the feedback system for controlling the dispensing of lubricant through the nozzles shown in FIG. 2, and
- FIG. 5 is a schematic view of a lubricating system for the switch plate of a switch.
- Referring to FIG. 1, a typical
yard track system 10 has ahump 12, across which is afeeder track 14. Feedertrack 14 passes afirst retarder 16 after which there is afirst switch 18 for dividing thetrack 14 into twotracks first switch 18 aresecondary switches secondary switches further switches yard tracks exit lead 46 across which the assembled trains are withdrawn. An incoming train is broken up by releasing cars over thehump 12 and allowing them to roll down thefeeder track 14 and into the yard tracks 36-42. - The
retarder 16 has a computer, not shown, which receives input from a speed detector, not shown, and from a scale, not shown, which categorizes the weight of the car. Using these two pieces of information and a look up table stored in its memory, the computer adjusts the resistant force applied by theretarder 16 to the wheels of the car. If a railroad car is not defective the car will be moving a the optimum speed when it leaves the retarder and it will move at a predictable speed down track to its destination provided the track has been properly lubricated. On the other hand, if the car is defective, either because the brake is being applied when it shouldn't be applied, or because the bearings of the wheels are worn, the car will leave the retarder at a significantly slower speed than the optimum speed and its progress as it moves through the yard will noticeably below the predicted speeds. - It should also be appreciated that a defective car, that is one having the brake applied when it shouldn't be applied, or having worn wheel bearings, will leave the retarder at a significantly slower speed than the optimum speed and the noticeably slow moving car can be detected and identified by the
first sensor 64. A defective car will also move through the system at a noticeably slower rate of speed. Defective cars are therefor identifiable by their reduced speed after leaving the retarder. - When an entire train is assembled on a yard track, the switches44-44 at the output end of the bowl are reconfigured to withdraw the assembled train out the
exit lead 46. - Referring to FIGS. 1 through 4, in accordance with the present invention, located behind the
first retarder 16 on thefeeder track 14 is alubricating station 50. The lubricatingstation 50 has asupply tank 52, apositive displacement pump 54 for ejecting the lubricant in thesupply tank 52, amotor 56 for operating thepump 54, and a network offeeder lines 58 for directing lubricant to a plurality of nozzles 60-60. Amicroprocessor 62 controls the operation of themotor 56 and thereby regulates the discharging of lubricant through the nozzles 60-60. Themicro processor 62 receives input form afirst sensor 64 which detects the speed of a car approaching thelubricating station 50 and from a plurality ofsecondary detectors - Referring further to FIG. 2 and3, in accordance with another feature of the invention, the dispensing system includes two mounting
bars 72, one positioned along the inner surface of each of the rails of atrack 74. Positioned along the length of each of the mountingbar 72 are the nozzles 60-60 which are of a type known in the art for dispensing lubricants. Each mountingbar 72 has alength 73 which is approximately equal to the circumference of a typicalrail car wheel 75 so that lubricant dispensed through the nozzle 60-60 on the mountingbar 72 will lubricate the entire circumference of thewheel 75 as it rolls across the lubricated portion oftrack 74. The wheels of the railroad car will then transport the lubricant down thefeeder track 14 to the selected yard track into which the car is directed. - The invention requires that the nozzles60-60 be positioned sufficiently close to one another and that the
pump 54 eject an adequate amount of lubricant on each application to apply a continuous path of lubricant along theentire length 73 of thetrack 74. We have found that the viscosity and other properties of the lubricant changes with temperature, and that the amount of lubricant being applied by the nozzles 60-60 is not constant unless thepump 54 is a positive displacement pump. By providing a positive displacement pump the desired amount of lubricant will be ejected through the nozzles 60-60 on each application. - It is desirable that the lubricant be evenly applied along the
length 73 of thetrack 74, however, the nozzles 60-60 of a dispensing system can become damaged from debris carried by the moving cars or the like. Damaged nozzles may partially restrict the flow of lubricant passing therethrough, and if they are all linked together they may not dispense the lubricant evenly on the track. To insure that the lubricant is evenly applied along thelength 73 of the mountingbar 72, eachnozzle 60 has an associatedvalve 76. The valves 76-76 are sequenced, such that eachvalve 76 is successively independently opened. All the lubricant dispensed by thepump 54 will then pass through only none nozzle at a time thereby insuring that the nozzle 60-60 all dispense an equal amount of lubricant. - Referring further to FIGS. 1 and 4 as a moving railroad car reaches the associated
yard track detector microprocessor 62 designating the arrival time of the car. Themicroprocessor 62 includes aclock 77 and amemory 78, and themicroprocessor 62 will divide the time that has elapsed from when the car crossed thefirst detector 64 to when it arrived at the secondary detector by the distance traveled to calculate an average speed for the car. If the average speed of a car entering a yard track 36-42 is below a predetermined desired speed stored in thememory 78 of the microprocessor but not excessively slow, themicroprocessor 62 will direct power to themotor 56 for operating thepump 54 and apply lubricant to the track when thewheels 75 of the next railroad car approaches thestation 50. If themicroprocessor 62 determines that the cars are rolling at the desired speed, it will not direct power to themotor 56 when the next railroad car approaches thereby controlling the further lubrication of the tracks. - The
microprocessor 62 is also responsive to arain detector 79 that detects when the tracks in the system are being lubricated by rain or snow. It is not necessary to lubricate wet tracks because water is an adequate lubricant. Accordingly thecomputer 62 is programmed to ignore readings from the detectors while the rain detector indicates the tracks are wet. The rain may, however, wash lubricant off the tracks, and therefore thecomputer 62 will initiate new calculations to determine track lubrication as soon as the tracks dry. Themicro processor 62 will therefor energize themotor 56 on information detected after the tracks have dried that show that cars are moving below the desired speeds. The microprocessor will also detect the presence of a potentially defective railroad car and notify thecentral office 88 as is further described below. - Referring to FIG. 1, the invention further includes
secondary lubrication stations switches switches secondary lubrication stations primary lubrication station 50, and has adetector first detector 64 of theprimary station 50, thedetectors secondary stations secondary lubrication station station 80 receives input only fromdetectors station 82 receives input only fromdetectors station 84 receives input only fromdetectors - The
secondary stations track system 10 and not to the entire system as does theprimary station 50, and are activated only after thecomputer 62 of theprimary lubricating station 50 determines that the access tracks are already adequately lubricated. For example, if a number of cars have been directed downtracks primary station 50. The cars directed to yard tracks 65 and 66 would then be rolling at the desired average speed and thestation 50 would not be applying lubricant to the tracks. If cars are subsequently directed to yard tracks 67 and 68, and these cars are found to have an average speed less than the desired speed, the loss in speed would presumably be due to inadequate lubrication of yard tracks 67 and 68. In this event themicroprocessor 62 of theprimary station 50 will not direct power to themotor 56 to further lubricate the tracks. The microprocessor of thesecondary station 82, however, will measure the time required for a car to pass from thedetector 83 associated with thestation 82 to thedown track detectors secondary station 82 will commence lubricating the tracks prior to the passing of each railroad car. The secondary station will continue to dispense lubricant to the tracks until the cars are again rolling at the desired speed, after which thesecondary station 82 will stop lubricating the tracks prior to the passage of a railroad car. - As can be seen, the present invention provides feedback from down track of the speed of the railroad car. Where the speed of the car is below a predetermined speed, the
lubricating stations track 74 immediately before the arrival of the next railroad car. The rolling cars will pick up the lubricant on the wheels thereof and apply it to the track as they move. The system will continue to dispense a fixed amount of lubricant on the tracks prior to the passing of a railroad car until themicroprocessors 62 of the various stations determine that the cars are rolling at speeds consistent with lubricated tracks, after which themicroprocessors 62 will terminate the dispensing of lubricant. - Referring to FIG. 4, a feature of the present invention is that it will identify potentially defective cars. It is far more expensive to deal with a defective car after it has been incorporated into a moving train than to repair the car while it is still in a yard.
- When the microprocessor determines that a car passing the
detector 64 is moving at either an excessively high speed or an exceptionally slow speed, themicroprocessor 62 of thevarious stations motor 56 to eject lubricant on the tracks in the path of the car. Themicroprocessor 62 will also ignore all information from the various sensors triggered by the car in determining whether lubrication is needed for succeeding cars thereby avoiding erroneous information into its calculations. Finally, the microprocessor will notify thecentral office 88 of an exceptionally slowly moving car that may be defective. - Referring to FIG. 5, the invention further includes a
lubrication station 90 positioned at eachswitch switch 18 includes a pair of non-parallel lengths of track having moveable end portions the distal ends of which are the switch points 106, 108. A switch normally has afirst switch point 106 contacting the track to which it is adjacent and asecond switch point 108 spaced from the track to which it is adjacent, and when the switch is thrown the switch points move until the first switch point is spaced from its adjacent track and the second switch point in contacting its adjacent track. To carry out this movement theswitch 18 has anelectric motor 91 and a drive system, not shown, that moves a plurality of slideable switch plates, all of which are identified generally at 96. When theswitch plates 96 are not lubricated they rapidly become worn and require replacement. When theswitch plates 96 are unlubricated themotor 91 will also draw a significantly greater amount of electric power to operate the switch than when it is lubricated. - In the absence of lubrication the switch points106, 108 of the
switch 18 rapidly become worn by the hundreds of wheels of the railroad cars that pass across the switch. Currently there is no automated system to mechanically lubricate the switch points 106, 108 or theswitch plates 96 of aswitch 18. The switch points and switch plates of existing systems are currently lubricated by hand and therefor there is a need for a method to mechanically lubricate these parts.Station 90 therefor has aprimary lubricating nozzle 100 aimed to direct lubricant onto theswitch plates 96 andsecondary nozzles - It should be appreciated that the switch points106, 108 become worn for different reasons than do the
switch plates 96. The frequent operation of theswitch 18 will cause rapid wear tounlubricated switch plates 96 without causing a similar amount of wear to the switch points 106, 108. On the other hand, the movements of hundreds of cars across the unlubricated switch points 106, 108 of a switch which is rarely operated will cause wear to the switch points 106, 108 without causing a corresponding amount of wear to theswitch plates 96. Theswitch plates 96 and the switch points 106, 108 of a railroad system are therefore subject to wear which may require costly repairs. - The
lubrication station 90 includes a reservoir, a positive displacement pump, and a motor (notmotor 91 of the switch), none of which are shown, similar to those discussed with respect to theprimary lubrication station 50. Thelubrication station 90 also includes ameans 98 for detecting the amount of current drawn by themotor 91 as it begins to move theswitch plates 96. The current being drawn by themotor 91 may be measured directly by means of an ammeter or the like, or indirectly by measuring the magnetic field that builds up around the power cable to themotor 91. The amount of current being drawn by themotor 91 is indicative of the amount of lubrication of theswitch plates 96, themotor 91 requiring significantly more power to operate unlubricated switch plates than lubricated switch plates. - The
station 90 further includes amicroprocessor 99 having a memory and stored in the memory is the maximum allowable amount of power that themotor 91 is permitted to draw. When the microprocessor determines that the power detected bymeans 98 exceeds the threshold maximum stored in the memory of the microprocessor 99 (exceeding the threshold being indicative of unlubricated switch plates) themicroprocessor 99 will direct power to the motor of thesystem 90 to send lubricant through theprimary nozzles 100 and lubricate theswitch plates 96. It should be appreciated that themicroprocessor 99 can detect that themotor 91 is drawing an excessive amount of power and the motor and pump of thestation 90 can direct lubricant to theswitch plates 96 before themotor 91 causes movement of theswitch plates 96. - As noted above, the switch points106, 108 and
switch plates 96 wear differently and the fact that theswitch plates 96 are unlubricated is a poor indicator of the condition of the switch points 106, 108. However, there presently is no suitable means for detecting the lubrication status of the switch points 106, 108, and in the absence of such a detection means, themicroprocessor 99 may also energize the motors and pumps to discharge lubricant through thesecondary nozzles - Preferably the
secondary nozzles - It should also be appreciated that there are other reasons besides lack of lubrication which may cause the
motor 91 to draw an excessive amount of current to move theswitch plates 96. For example, the drive system between themotor 91 and theswitch plates 96 may have become damages, or the moveable portions of track may have become bent. Themicroprocessor 99 is therefor programmed to notify the central office that theswitch 18 is potentially defective if, after it has lubricated the switch plates 96 a number of times, themeans 98 continues to detect that themotor 91 is continuing to draw an excessive current to move theswitch plates 96. - Although the
microprocessor 99 has been described as responding to a signal from ameans 98 for detecting the amount of current drawn by themotor 91, themicroprocessor 99 could also be programmed to initiate an application of lubricant each time the switch is thrown without regard to the amount of power drawn by themotor 91. In this case a pair ofdetectors switch plates 96 would be suitable to signal themicroprocessor 99 that theswitch 18 has been thrown. Lubricating the switch plates each time the switch is thrown may be suitable for an infrequently used switch, but it may lead to over lubrication of a frequently used switch. - While the invention has been described with respect to a single embodiment, many modifications and variations can be made without departing from the true spirit and scope of the invention. It is, therefore, the intent of the appendant claims to cover all such modifications and variations which fall within the true spirit and scope of the invention.
Claims (19)
1. The method of lubricating the switch plates of a railroad switch where said switch plates are moveable between a first position in which said switch will direct a rolling railway car to a first track and a second position in which said switch will direct a rolling railway car to a second track, said method comprising the steps of
providing means for generating a signal in response to said switch plate being moved to said first position,
providing a reservoir of lubricant,
providing a pump and a nozzle for dispensing said lubricant,
positioning said nozzle to direct a flow of lubricant to said switch plates, and
providing means for actuating said pump to dispense lubricant through said nozzle in response to said means for generating a signal.
2. The method of claim 1 and further comprising the steps of
providing a second means for generating a signal in response to said switch plates being moved to said second position, and
said means for actuating said pump also being responsive to said second means for generating a signal.
3. The method of lubricating the switch plates of a railroad switch where said switch plates are moveable between a first position in which said switch will direct a rolling railway car to a first track and a second position in which said switch will direct a rolling railway car to a second track, said switch being operated by an electric motor, said method comprising the steps of
providing means for generating a signal in response to the amount of power drawn by said electric motor,
providing a memory,
recording in said memory a maximum power draw for said electric motor,
comparing the amount of power drawn by said electric motor as shown by said means for generating to said maximum power draw in said memory,
providing means to dispense lubricant said switch plates in response to a second signal,
generating a second signal to actuate said means for dispensing when said power drawn by said electric motor as shown by said means for generating exceeds said maximum power draw as recorded in said memory.
4. The method of claim 3 wherein said pump is a positive displacement pump.
5. The method of claim 3 wherein said switch has a switch point, said method comprising the further steps of
providing means for lubricating said switch point in response to said second signal.
6. The method of claim 3 and comprising the further step of
notifying a central office in the event the amount of power drawn by said motor as shown by said means for generating exceeds said maximum power draw in said memory each time said motor is activated for a give number of successive activations.
7. The method of claim 3 wherein said means for generating a signal in an ammeter.
8. The method of claim 3 wherein said means for generating a signal measures a change in an electric field.
9. The method of lubricating the switch point of a railroad switch where said switch point is moveable between a first position in which said railroad switch will direct a rolling railway car to a first track and a second position in which said railroad switch will direct a rolling railway car to a second track, said railroad switch preceded by a length of railroad track, said method comprising the steps of
providing a reservoir of lubricant,
providing a pump and a nozzle for dispensing said lubricant,
positioning said nozzle to direct a flow of lubricant to said length of track preceding said switch point, and
providing means for actuating said pump to dispense lubricant through said nozzle in response to a signal.
10. The method of claim 9 and further including the steps of
providing means for generating a signal in response to said switch point being moved to said first position wherein said means for actuating is responsive to said signal from said means for generating.
11. The method of claim 9 including the step of directing said nozzle to direct a flow of lubricant to the top of said track.
12. The method of claim 9 including the step of positioning said nozzle to direct a flow of lubricant to said track at a point on said railroad track that precedes said switch plate by approximately one revolution of a wheel of a railroad car.
13. The method of lubricating a length of railroad track comprising the steps of
providing a plurality of nozzles,
spacing said nozzles along said length of track,
directing said nozzles to dispense lubricant to a surface of said length of track,
providing a reservoir of lubricant and a pump for pumping said lubricant,
providing a piping means for piping said lubricant to said plurality of nozzles,
providing valves means along said piping means for controlling the flow of lubricant to said plurality of nozzles, and
providing sequencing means for controlling said valve means wherein said flow of lubricant is directed to one of said plurality of nozzles at a time.
14. The method of identifying as potentially defective a railroad car as it moves along a length of railroad track of a switchyard comprising the steps of
providing means for lubricating said length of railroad track,
providing means for controlling the initial speed of a railroad car that is directed along said length of railroad track,
directing said car along said length of railroad track at a predetermined initial speed,
providing means for calculating an average speed of said railroad car as it moves along said length of railroad track,
providing a computer including a memory,
storing in said memory a look up chart of expected average speeds over said length of track for railroad cars moving on lubricated tracks at various initial speeds,
calculating an average speed of said car as it moves across said length of track,
comparing said calculated average speed to said expected average speed from said look up chart, and
if said calculated average speed of said railroad car is less than said expected average speed, identifying said car as potentially defective in order that it may be inspected.
15. The method of claim 14 and comprising the further step of notifying the central office of a defective car.
16. The method of claim 14 wherein said means for controlling the initial speed of a railroad car comprises a retarder.
17. The method of lubricating a length of railroad track comprising the steps of
providing means for lubricating said length of railroad tracks,
providing a computer for controlling said means for lubricating,
providing detector means for detecting a measurable characteristic of a railroad car moving along said length of railroad track where said measurable characteristics is useable to determine whether said length of railroad tracks is lubricated,
providing a memory for said computer,
storing in said memory a look up chart of said characteristics for a railroad car moving along said length of railroad tracks while said railroad tracks are lubricated,
providing means for detecting when said railroad tracks are moist, and
comparing measured characteristics of a moving railroad car to characteristics in said look up chart as a measure of track lubrication only while said railroad tracks are not moist.
18. The method of claim 17 wherein an average speed of a railroad car is the measurable characteristic indicative of lubricated railroad tracks.
19. The method of identifying as potentially defective a railroad car as it moves along a length of railroad track comprising the steps of
providing means for lubricating said length of railroad track,
providing a retarder for controlling the initial speed of a railroad car that are directed along said length of railroad track,
directing said car along said length of railroad track,
using said retarder to apply a predetermined amount of resistance to said moving car to reduce the speed of said car to an optimum initial speed,
providing means for determining the speed of said car,
positioning said means for determining speed after said retarder,
providing a computer including a memory,
storing in said memory a look up chart of expected initial speeds for railroad cars leaving said retarder in response to the operation of said retarder,
using said means for determining speed to find a speed of said car,
comparing said determined speed to said expected initial speed from said look up chart, and
if said determined speed of said railroad car is less than said expected initial speed, identifying said car as potentially defective in order that it may be inspected.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/238,451 US20030010571A1 (en) | 2000-08-07 | 2002-09-10 | Method and apparatus for lubricating railroad tracks |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/633,390 US6446754B1 (en) | 2000-08-07 | 2000-08-07 | Method and apparatus for lubricating railroad tracks |
US10/238,451 US20030010571A1 (en) | 2000-08-07 | 2002-09-10 | Method and apparatus for lubricating railroad tracks |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/633,390 Continuation-In-Part US6446754B1 (en) | 2000-08-07 | 2000-08-07 | Method and apparatus for lubricating railroad tracks |
Publications (1)
Publication Number | Publication Date |
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US20030010571A1 true US20030010571A1 (en) | 2003-01-16 |
Family
ID=46281172
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/238,451 Abandoned US20030010571A1 (en) | 2000-08-07 | 2002-09-10 | Method and apparatus for lubricating railroad tracks |
Country Status (1)
Country | Link |
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US (1) | US20030010571A1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7096997B2 (en) | 2002-06-13 | 2006-08-29 | Portec, Rail Products Ltd. | Trackside friction management digital control system |
US20070026205A1 (en) * | 2005-08-01 | 2007-02-01 | Vapor Technologies Inc. | Article having patterned decorative coating |
US20140318897A1 (en) * | 2012-01-28 | 2014-10-30 | Bojan Pavcnik | Line distributor, preferably for anti-noise device for rail brakes |
US20230382441A1 (en) * | 2022-05-25 | 2023-11-30 | Rbl, Inc. | Automatic switch plate lubrication assembly |
Citations (4)
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US2929466A (en) * | 1958-03-17 | 1960-03-22 | Railway Maintenance Corp | Rail flange lubricator |
US5842543A (en) * | 1995-10-24 | 1998-12-01 | Nabco Limited | Lubricant supply apparatus for railroad turnout |
US6446754B1 (en) * | 2000-08-07 | 2002-09-10 | Kevin Kostelny-Vogts | Method and apparatus for lubricating railroad tracks |
US20030111295A1 (en) * | 2001-12-17 | 2003-06-19 | Kumar Ajith Kuttannair | Wayside rail lubrication apparatus and method |
-
2002
- 2002-09-10 US US10/238,451 patent/US20030010571A1/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2929466A (en) * | 1958-03-17 | 1960-03-22 | Railway Maintenance Corp | Rail flange lubricator |
US5842543A (en) * | 1995-10-24 | 1998-12-01 | Nabco Limited | Lubricant supply apparatus for railroad turnout |
US6446754B1 (en) * | 2000-08-07 | 2002-09-10 | Kevin Kostelny-Vogts | Method and apparatus for lubricating railroad tracks |
US20030111295A1 (en) * | 2001-12-17 | 2003-06-19 | Kumar Ajith Kuttannair | Wayside rail lubrication apparatus and method |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7096997B2 (en) | 2002-06-13 | 2006-08-29 | Portec, Rail Products Ltd. | Trackside friction management digital control system |
US20070026205A1 (en) * | 2005-08-01 | 2007-02-01 | Vapor Technologies Inc. | Article having patterned decorative coating |
US20140318897A1 (en) * | 2012-01-28 | 2014-10-30 | Bojan Pavcnik | Line distributor, preferably for anti-noise device for rail brakes |
US9409582B2 (en) * | 2012-01-28 | 2016-08-09 | Bojan Pav{hacek over (c)}nik | Line distributor, preferably for anti-noise device for rail brakes |
US20230382441A1 (en) * | 2022-05-25 | 2023-11-30 | Rbl, Inc. | Automatic switch plate lubrication assembly |
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Legal Events
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