Abstract:
One embodiment of the invention relates to an apparatus for configuring a wheel associated with a train. The apparatus comprises a tool configured to engage the wheel; a compound slide system for positioning the cutting tool in at least two axes; and a computer control coupled to control the compound slide system. The compound slide system is controlled so that the wheel is configured in accordance with a profile.

Description:
FIELD 
       [0001]    The present disclosure relates generally to the field of maintenance for railway vehicles. More specifically, the present disclosure relates to an apparatus for machining and maintaining the wheels of a locomotive or railway car. 
       BACKGROUND OF THE INVENTION 
       [0002]    Wheels on railway locomotives and cars are subject to abuse and wear in the course of normal use. This wear changes the contour of the wheel, forming undesirable contours including flats, high flanges and other contours that adversely affect the performance of the wheel. A worn wheel can reduce ride quality, increase the risk of derailments, and contribute to increased wear, fatigue, noise, and excessive fuel consumption. 
         [0003]    Locomotive and railcar wheel maintenance is important to safety and efficient operation of railways. Locomotive and railcar wheel maintenance typically involves removing the locomotive or railcar from service and re-profiling or “retruing” the wheel with a lathe mechanism. Such known lathe mechanisms may be provided in pits below removable rail sections. Such mechanisms may be computer numerical control (CNC) machines and are generally large, expensive, and not portable. Stationary mechanisms require establishing a permanent maintenance facility or area and removing the locomotive or railcar from service. 
         [0004]    Locomotive and railcar wheels may also be re-profiled with manual lathe mechanisms. However, such manual processes are generally time-consuming and require intense labor, taking as many as 8 hours to re-profile a pair of wheels. In addition, some known processes create a long, continuous chip. A machinist is required to wear safety gear such as heavy leather clothing and a face shield to avoid being injured by the extremely hot, razor sharp chips. 
         [0005]    Thus, there is a need for a portable re-profiling system for wheels of locomotives or railcars. Furthermore, there is a need for a lathe mechanism that is more efficient and safer than manual lathe mechanisms. Further still, there is a need for an automated re-profiling system that is quick, efficient and less expensive than conventional systems located in permanent maintenance facilities. 
       SUMMARY OF THE INVENTION 
       [0006]    One embodiment of the invention relates to an apparatus for configuring a wheel associated with a train. The apparatus comprises a cutting tool or a grinding tool configured to engage the wheel; a compound slide system for positioning the cutting tool in at least two axes; and a computer control coupled to control the compound slide system. The compound slide system is controlled so that the wheel is configured in accordance with a profile. 
         [0007]    Another embodiment relates to a method of profiling a wheel while attached to a railcar or locomotive on a rail. The method comprises disengaging the wheel from the rail. The wheel is ordinarily attached to the railcar or locomotive. The method also includes attaching a portable mill or lathe machine to the track; rotating the wheel; and profiling the wheel in accordance with a stored profile in the portable mill or lathe machine. 
         [0008]    Still another embodiment relates to a system for profiling a wheel in accordance with an electronically stored profile. The wheel is associated with a train. The system comprises a lathe cutting tool configured to engage the wheel; a compound positioning system for positioning the cutting tool in at least two axes; and a computer control for controlling the compound positioning system. The compound system is controlled so that the wheel is shaped in accordance with the profile. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a an isometric view of a railroad car according to an exemplary embodiment. 
           [0010]      FIG. 2  is a block diagram of an apparatus for re-profiling a wheel for a railroad car of  FIG. 1  according to an exemplary embodiment. 
           [0011]      FIGS. 3A and 3B  are isometric views of an apparatus for re-profiling a wheel for a railroad car of  FIG. 1  according to an exemplary embodiment. 
           [0012]      FIG. 4  is top view of the apparatus of  FIG. 2  for re-profiling a wheel for a railroad car. 
           [0013]      FIG. 5  is a bottom isometric view of the apparatus of  FIG. 2 , showing a mechanism for coupling the apparatus to a rail. 
           [0014]      FIGS. 6-7  are isometric views of a drive mechanism for the apparatus of  FIG. 2  according to one exemplary embodiment. 
           [0015]      FIG. 8  is an isometric view of a cutting tool for the apparatus of  FIG. 2  according to an exemplary embodiment. 
           [0016]      FIGS. 9A-9B  are top views of two exemplary wheel profiles for a wheel for the railcar of  FIG. 1 . 
           [0017]      FIG. 10  is a flowchart of a method for profiling a wheel according to an exemplary embodiment. 
           [0018]      FIG. 11  is a top view of an apparatus for re-profiling a wheel for a railroad car according to another exemplary embodiment. 
           [0019]      FIG. 12  is a front view of a drive mechanism for an apparatus for re-profiling a wheel for a locomotive according to an exemplary embodiment. 
           [0020]      FIGS. 13 and 14  are isometric views of a drive mechanism for an apparatus for re-profiling a wheel for a railroad car according to another exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    Referring in general to the FIGURES and more specifically to  FIGS. 2-4 , an apparatus  20  for profiling or re-profiling the wheels  12  of a railcar  10  is shown according to an exemplary embodiment. For the purpose of this specification and the claims, railroad cars include any wheeled systems configured for riding on railroad tracks or rails, including, for example, a locomotive  11  and a railcar  10  shown in  FIG. 1 . Apparatus  20  is a computer controlled lathe apparatus that is configured to be coupled to tracks  18  upon which locomotive  11  or railcar  10  rides. 
         [0022]    Apparatus  20  is a portable lathe device that is configured to be coupled to the track or rail  18  upon which wheels  12  of a railcar  10  are resting. To provide a precise profile for wheel  12  with a relatively short cycle time, apparatus  20  is a computer numerical control (CNC) lathe. The desired profile  82  for wheel  12  and the cutting path needed to provide the profile for wheel  12  is stored in a computer control  80  coupled to apparatus  20 . Apparatus  20  includes a cutting tool  24  with an insert  26 . A profile for wheel  12  is provided by rotating wheel  12  and moving cutting tool  24  relative to wheel  12  with a 2-axis slide mechanism  30 . A user may operate an interface  84  coupled to computer controller  80  to control apparatus  20 . 
         [0023]    Apparatus  20  is able to be easily moved to a railcar  10  or locomotive  11  anywhere instead of having to move the railcar  10  or locomotive  11  to apparatus  20 . While most existing mechanisms can weigh in access of several tons, apparatus  20  weighs approximately 450 lbs. Apparatus  20 , for example, may be used to service a railcar  10  or locomotive  11  that is broken down at a location away from a station or service area. According to one exemplary embodiment, apparatus  20  wheels may be coupled to apparatus  20 . According to another exemplary embodiment, apparatus  20  may be transported by a vehicle such as a forklift. 
         [0024]    As shown best in  FIG. 5 , apparatus  20  is coupled to rail  18  with a mounting mechanism  90 . Mounting mechanism  90  rides on the top of a rail  18  aligned with a wheel  12  to be machined. Mounting mechanism  90  is configured to support apparatus  20  such that apparatus is level, firmly coupled to rail  18 , and rotated to be aligned with wheel  12 . According to an exemplary embodiment, mounting mechanism  90  includes a plate or main body  92 , one or more clamps  96 , a location bar  100 , and a push bar  108 . 
         [0025]    Location bar  100  is placed along the edge of rail  18  to locate apparatus  20  above rail  18  (e.g., so that the apparatus  20  is approximately aligned with rail  18 ). Wheels  12  and axle  14  may be configured to rotate slightly about a vertical axis (e.g., to facilitate railcar  10 ,  11  moving along curved rails). When railcar  10 ,  11  is elevated from rails  18 , wheels  12  and axle may rotate about this horizontal axis. The magnitude and direction of this rotation is generally unpredictable. To compensate for the rotation and to align apparatus  20  with wheel  12 , location bar  100  is coupled to plate  92  with a pinned connection (not shown) provided generally in the middle of location bar  100 . Location bar  100  includes one or more holes  102 , that are aligned with corresponding slots  104  ( FIG. 4 ) in plate  92 . Once apparatus  20  is rotated so it is aligned with wheel  12 , fasteners passing through holes  102  are tightened to prevent apparatus  20  from rotating about the pinned connection of location bar  100 . 
         [0026]    Clamps  96  are movable in a direction generally perpendicular to rail  18 . Clamps  96  are coupled to plate  92  by a fastener that passes through a hole  98  in clamp  96  and a corresponding slot  94  in plate  92 . According to one exemplary embodiment, clamps  96  are coupled to plate  92  with a bolt that engages a nut. As the bolt is tightened, the head of the bolt and the nut compress clamp  96  against plate  92 , preventing clamp  96  from moving relative to plate  92 . When apparatus  20  is placed on rail  18 , clamps  96  are moved to compress rail  18 . A push rod  108  ( FIG. 12 ) is provided to limit the movement of apparatus  20  perpendicular to rail  18 . One end of push rod  108  is coupled to apparatus while the opposite end extends to contact the opposite rail  18  (e.g. the rail apparatus  20  is not resting on) or another suitable stationary object. 
         [0027]    According to one exemplary embodiment, apparatus  20  is leveled (e.g., so cutting tool  24  moves along a horizontal plane). A multitude of threaded holes  106  are provided about the periphery of plate  92 . Holes  106  receive leveling mechanisms such as threaded rods (not shown) with an end that contacts the ground. By turning the leveling mechanisms, they move in a vertical direction relative to plate  92  and move various portions of plate  92  and, in turn, apparatus  20 , up or down. According to one exemplary embodiment, holes  106  are provided at each corner of plate  92 . According to other exemplary embodiments, holes  106  may be provided elsewhere (e.g., along a side of plate  92 ). 
         [0028]    As shown best in  FIG. 8 , cutting tool  24  includes an insert  26  that is secured with an insert clamp  28  (e.g., retainer, holder, etc.). The edges of wheels  12  being profiled may include imbedded sand, stones, and other foreign debris. Cutting tool  24  includes a high-quality cutting tool insert  26  that is able to withstand the wear from the imbedded particles. According to one exemplary embodiment, insert  26  is formed from a tungsten carbide material. According to other exemplary embodiments, insert  26  may be formed from cermet, a coated carbide, a ceramic material, or any other suitable material known in the art. While insert  26  is shown as a generally cylindrical member in  FIGS. 3 and 8 , according to other exemplary embodiments it may have a wide variety of geometries. 
         [0029]    Wheel  12  is turned so cutting tool  24  can profile the entire circumference of wheel  12  with a drive mechanism  50 . Drive mechanism  50  includes a base  51 , power source such as drive motor  52 , a gear reducer  54 , and a sprocket  56  coupled to a wheel  12  opposite of the wheel  12  to be profiled (e.g. on the same axle  14 ). Sprocket  56  is bolted or otherwise coupled to the end of wheel  12  opposite of wheel  12  to be profiled. Because both wheels  12  are mounted on the same solid axle  14 , turning one wheel also turns the other. Gear reducer  54  is provided between drive motor  52  and sprocket  56  to reduce the rotational speed to wheel  12  and increase the torque to wheel  12 . The output shaft of gear reducer  54  is coupled to sprocket  56  with a chain  58 . According to other exemplary embodiments, wheel could be driven by other means (e.g., a motor coupled directly to the wheel, with a roller contacting the edge of the wheel, etc.). According to an exemplary embodiment, wheel  12  I turned a approximately 30-40 revolutions per minute. According to other exemplary embodiments, wheel  12  may be turned a another rate depending on a variety of factors, including the cutting tool material, cutting tool geometry, motor speed, etc. According to one exemplary embodiment, drive motor  52  is a 15 hp AC motor and gear reducer  54  provides a gear reduction ration of 40:1. 
         [0030]    Referring to  FIGS. 13 and 14 , according to another exemplary embodiment, a drive mechanism  150  uses a friction wheel to turn wheel  12  and axle  14 . Drive mechanism is similar to drive mechanism  50 , but includes a drive motor  152  that turns a friction wheel such as a rubber roller  157 . Roller  157  is compressed against a wheel  12  opposite of the wheel  12  to be profiled (e.g. on the same axle  14 ). A gear reducer may be provided between drive motor  152  and roller  157 . Roller  157  is rotated by motor  152  and, in turn, rotates wheels  12  and axle  14 . 
         [0031]    Cutting tool  24  is coupled to a slide mechanism  30  that allows cutting tool  24  to be movable relative to wheel  12  along both an x-axis  40  and a y-axis  42 . Slide mechanism includes a first slide  31  that moves along x-axis  40 , parallel to axle  14 , and a second slide  35  that moves along y-axis  42 , perpendicular to axle  14 . A first power source  32  is provided to move first slide  31 . A second power source  36  is provided to move second slide  35 . As described above, according to one exemplary embodiment, apparatus  20  is a CNC lathe, and power sources  32  and  36  are electric motors (e.g., servo motors, stepper motors, etc.) that are controlled with signals from a computer controller. Power sources  32  and  36  are coupled to gear reducers  33  and  37 , respectively. Gear reducers  33  and  37  reduce the shaft speed and increase the torque from power sources  32  and  36 . According to various exemplary embodiments, gear reducers  33  and  37  may be directly coupled to the slide mechanism or may be coupled to the slide mechanism through a transfer mechanism. 
         [0032]    As shown according to one exemplary embodiment in  FIG. 3 , power source  32  and gear reducer  33  are coupled directly to the threaded drive shaft  110  for first slide  31  while power source  36  and gear reducer  37  are coupled to the threaded drive shaft  112  of second slide  35  through transfer mechanism  38 . Transfer mechanism  38  may be any mechanism that suitably transfers rotational power, such as a belt and pulley mechanism, a chain and sprocket mechanism, or a gear set. According to an exemplary embodiment, transfer mechanism  38  includes a timing belt (not shown) that engages two pulleys. Transfer mechanisms may be provided to reposition power sources (e.g., to provide a more compact apparatus  20 ), and/or, to further lower or raise the rotational speed of the drive shafts for slide mechanism  30  (e.g., by providing two differently sized pulleys or sprockets or a reducing gear set). A guard or casing (not shown) may be provided to prevent inadvertent contact between a person or object and the moving components of transfer mechanism  38 . According to one exemplary embodiment, power sources  32  and  36  are servo motors and gear reducers  33  and  37  are 20:1 gear reducers. According to other exemplary embodiments, power source  32  and  36  may be a hand wheel with tracer system. 
         [0033]    Second slide  35  may be configured to rotate about a vertical axis relative to base  22  and mounting mechanism  90 . According to an exemplary embodiment, second slide  35  can be locked at two positions 180 degrees apart to service both wheels  12  on axle  14  while engaging the inside edge of either rail  18  by reorienting mounting mechanism  90  relative to second slide  35 . 
         [0034]    As cutting tool  24  profiles wheel  12 , it may form a chip of removed material. Because apparatus  20  profiles wheel  12  with an automated CNC process, a user does not need to be in close proximity to wheel  12  as it is being machines, reducing the chance of the user being cut by the chip. 
         [0035]    Referring now to  FIG. 10 , a method for profiling wheels  12  on a railcar  10  or locomotive  11  involve first disengaging wheels  12  from rails  18  (step  70 ). According to an exemplary embodiment, a jack or lift  19  ( FIG. 12 ) is used to raise one set of wheels  12  off of rails  18  while leaving the other set of wheels engaged. Wheels  12  and axle  14  are both left coupled to railcar  10  or locomotive  11  to reduce the amount of time needed to profile wheels  12 . 
         [0036]    After wheels  12  have been disengaged from rails  18 , apparatus  20  is coupled to rails  18  proximate to a wheel  12  with mounting mechanism  90  (step  72 ). The position of cutting tool  24  relative to wheel  12  is calibrated by first touching cutting tool  24  to wheel  12  at several places and storing those positions in the computer controller. According to one exemplary embodiment, as shown in  FIGS. 9A and 9B , cutting tool  24  is touched to wheel  12  at four places. A first point  60  is on top of the flange  13  of wheel  12 . A second point  62  is on the outside edge or “rim”  17  of wheel  12 . A third point  64  and a fourth point  66  are on the two contact points of the “tread”  15 . 
         [0037]    Wheel  12  is rotated so cutting tool  24  can profile the entire circumference of wheel  12  (step  74 ). If  11  is a locomotive, wheel  12  may be a driving wheel. However, powering the locomotive would cause all the driving wheels on locomotive  11  to turn. To turn only the wheel being profiled by apparatus  20 , an external power source is used. According to one exemplary embodiment, shown in  FIG. 12 , wheel  12  is turned by powering the traction motor  122  with a portable power source  120  such as a DC welder. If railcar  10  is an unpowered car, such as a box car, wheel  12  is turned by a chain and sprocket drive mechanism  50 , as shown in  FIGS. 6 and 7  or a friction wheel drive mechanism  150 , as shown in  FIGS. 13 and 14 . 
         [0038]    With wheel  12  rotating, cutting tool  24  profiles wheel  12  in accordance with a stored profile  82  in the computer controller  80  (step  76 ). Cutting tool  24  is moved by slide mechanism  35  along x-axis  40  and y-axis  42  with drive motors  32  and  36 . According to one exemplary embodiment, apparatus  20  may be used to machine wheel  12  to an AAR-IB regular flange profile ( FIG. 9A ) or an AAR-IB narrow flange profile ( FIG. 9B ). According to other exemplary embodiments, the computer controller may provide other paths to apparatus  20  to machine wheel  12  to another profile. 
         [0039]    Once wheel  12  has been profiled by apparatus  20 , railcar  10  or locomotive  11  is lowered back onto rails  18  (step  78 ). Railcar  10  or locomotive  11  may then be raised again to profile the other wheels or, if all wheels have been profiled, railcar  10  or locomotive  11  may be returned to service. 
         [0040]    Referring now to  FIG. 11 , according to another exemplary embodiment, apparatus  20  used to profile wheel  12  is not a CNC lathe. Instead, a template  122  provides a path for cutting tool  24  of apparatus  20  while an operator moves cutting tool  24  with a manual slide mechanism  130 . A hand wheel  132  is turned to move first slide  31  along drive shaft  110  and a second hand wheel  136  is turned to move second slide  35  along drive shaft  112 . Template  122  includes a profile  124  that describes a desired profile for wheel  12 . Template  122  is positioned relative to wheel  12  such that an arm  120  extending from apparatus  20  contacts template  122  at a position analogous to the position of cutting tool  24  relative to wheel  12 . The position of template  122  is calibrated by first touching cutting tool  24  to wheel  12  at several places and positioning template  122  such that arm  120  contacts template  122  at the same places. The calibration points may be similar to the calibration points used to calibrate the CNC process described above or may be different points. 
         [0041]    For the purpose of this disclosure, the term “coupled” means the joining of two members directly or indirectly to one another. Such joining may be stationary in nature or moveable in nature. Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another. Such joining may be permanent in nature or may be removable or releasable in nature. 
         [0042]    It is important to note that the construction and arrangement of the wheel mill as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments of the present inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages presented in the present application. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present disclosure.