Abstract:
The present disclosure generally relates to a railroad chassis vehicle having independently operable workheads for carrying out rail maintenance operations on non-uniform sections of railroad tracks. Related methods of operation of the railroad chassis and associated maintenance of ballast beds underlying railroad tracks are also described.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 62/235,648 filed on Oct. 1, 2015, the disclosure of which is hereby incorporated by reference in entirety. 
     
    
     BACKGROUND 
       [0002]    Railroads are typically constructed to include a pair of elongated, substantially parallel rails, which are coupled to a plurality of laterally extending rail ties. The rail ties are disposed on a ballast bed of hard particulate material such as gravel and are used to support the rails. Over time, normal wear and tear on the railroad may cause the rails to deviate from a desired profile based on movement of the underlying ballast, and as such voids or gaps under the rail ties may appear. 
         [0003]    The traditional method of fixing voids that appeared under rail ties was very labor and time intensive, as it required measurement of the voids under each individual rail tie, manually lifting the rail ties, and then spreading a pre-measured quantity of ballast under the rail ties to raise the rails. In the 1970s, British Rail developed a mechanization of the traditional method by modifying a tamper and installing a system for distributing ballast under the rail tie with blasts of compressed air, creating the first stoneblower. 
         [0004]    Modern stoneblowers are typically wheeled cars that comprise a track lifting device, a supply of crushed ballast rock, a source of compressed air, and a number of workheads. Each workhead carries a pair of blowing tubes. In operation, the track lifting device raises the track rails and the underlying rail ties to which the rails are secured. The workhead forces the blowing tubes into the ballast adjacent the raised rail ties with each pair of blowing tubes straddling a track rail. Stone is then blown through the blowing tubes into the voids beneath the raised rail ties. The workhead withdraws the blowing tubes and the track rail and rail ties are lowered. The stoneblower then advances to the next set of rail ties and repeats this procedure. 
         [0005]    Modern stoneblowers are designed to restore a track&#39;s vertical and lateral alignment to an accuracy of 1.0 mm without disturbing the pre-existing compacted ballast layer. Vehicle bogies allow stoneblowers to measure a loaded track profile, and therefore measure the voids in the ballast under each rail tie. Computers then calculate the quantity of ballast to be “blown” under each rail tie, thus minimizing stone usage based on the track category or speed limit. 
         [0006]    Compared with tamping, stoneblowers advantageously can be used on high speed track lines, treat only the areas of the track that need treatment, and reduce ballast damage. Further, after stoneblowing, the track does not become more rigid because the stoneblower only treats areas that need treatment, while the majority of the rail ties are supported on the original ballast and railroad bed. In addition, a new rock supplier is not needed to use a stoneblower for track maintenance. The injected ballast often comes from the same quarries and has the same attrition values as normal ballast. Additionally, using small, crushed stones as ballast causes less damage to the underside of the rail ties because the small stone is less likely to fail under heavy axle load based on increased surface area. 
         [0007]    Current stoneblowers have some drawbacks, however, based on the current design incorporating pairs of parallel blowing tubes. For example, modern stoneblowers cannot efficiently blow ballast under non-uniform sections of rails, such as at railroad frogs or crossings, because the pairs of blowing tubes are only configured to have blowing tubes on each side of a rail and/or on each side of a rail tie, but they cannot blow ballast directly under the frog and/or under the rail tie area directly under the frog. However, in the continually changing world of track maintenance, it is essential that rail companies be able to provide quality track maintenance and alignment equipment that can service all sections of rail, not just uniform sections of rail. Moreover, conventional stoneblowers are large vehicles that are expensive to manufacture, deploy and operate. Smaller stoneblower machines, including those that can be deployed to work small areas of rail, such as frogs, are needed. Therefore, an improved stoneblower is desired. 
       BRIEF SUMMARY 
       [0008]    The present disclosure generally relates to an improved stoneblower system comprising a railroad chassis for performing ballast maintenance on sections of non-uniform railroad track, such as railroad frogs or other intersections. The railroad chassis includes a plurality of workheads that are independently operable (e.g., movable). Each of the workheads includes one or more blowing tubes for dispensing ballast stones into a bed of ballast stones underlying rail ties of a railroad track. The one or more blowing tubes may be lowered into the bed of ballast stone so that new ballast stone may be dispensed into cavities in the bed of ballast stone below the rail ties. Dispensing new ballast stone into the bed of ballast stone raises the height of the bed of ballast stone, thereby raising the height of the overlying rail ties and rails of the railroad tracks. In this manner, alignment of the railroad tracks may be improved and/or maintained. The blowing tubes may similarly be independently operable with respect to the workheads (e.g., rotatable with respect to the workheads) so that new ballast may be accurately dispensed in difficult-to-reach locations of the non-uniform railroad track. Various hardware elements may be used to control positioning of the workheads and the blowing tubes. Additionally, a computing system may be utilized to collect and analyze measurements associated with the railroad track to ensure appropriate amounts of ballast stone are dispensed in particular locations. Related methods for operating the railroad chassis are also described. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Reference is now made to the following descriptions taken in conjunction with the accompanying drawings. 
           [0010]      FIG. 1  illustrates a perspective view of an exemplary stoneblower system according to the present disclosure. 
           [0011]      FIG. 2  illustrates a perspective view of an exemplary railroad chassis of the stoneblower system of  FIG. 1 . 
           [0012]      FIG. 3  illustrates a perspective view of a workhead and associated blowing tube associated with the associated with the railroad chassis of  FIG. 2 . 
           [0013]      FIG. 4  illustrates a perspective view of a track reference device associated with the railroad chassis of  FIG. 2 . 
           [0014]      FIG. 5  illustrates a perspective view of a third point lifting arm associated with the railroad chassis of  FIG. 2 . 
           [0015]      FIG. 6  illustrates a perspective view of a railroad chassis associated with the railroad stoneblower system of  FIG. 1 . 
           [0016]      FIG. 7  illustrates a top view of an exemplary railroad frog intersection according to the present disclosure. 
           [0017]      FIG. 8  illustrates a cross-sectional side view of an exemplary stoneblowing process according to the present disclosure. 
           [0018]      FIG. 9  illustrates a computing system for carrying out processes described herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Various embodiments of an improved stoneblower are described according to the present disclosure. It is to be understood, however, that the following explanation is merely exemplary in describing the devices and methods of the present disclosure. Accordingly, several modifications, changes, and substitutions are contemplated. 
         [0020]    In an embodiment, and as shown in  FIG. 1 , an improved stoneblower system  100  may comprise a rail maintenance vehicle  102  and a railroad chassis  104 . In some embodiments, the railroad chassis  104  may be towed behind the rail maintenance vehicle  102  as the rail maintenance vehicle  102  propels itself along rails  106  of a railroad track. In other embodiments, the railroad chassis  104  may be self propelled and thus may include an engine  107  (e.g., a propulsion system and/or operating system) for propelling the railroad chassis  104  along the rails  106  of the railroad track. In still other embodiments, the railroad chassis  104  may be operated as a drone vehicle with no on-board personnel. In further embodiments, the railroad chassis  104  may take the form of a road-rail chassis or by-rail vehicle, which may be operated on both roads and rail. The rail maintenance vehicle  102  and/or the railroad chassis  104  of the stoneblower system  100  may include a plurality of wheels for engaging and moving along a top surface of the rails  106 . 
         [0021]    As described throughout, the railroad track may include a pair of elongated, substantially parallel rails  106 , which may be coupled to a plurality of laterally extending rail ties  108 . In some embodiments, a top surface of each rail tie  108  may be coupled to a bottom surface of the rails  106 . The rail ties  108  may be disposed on a ballast bed  110  of hard particulate material such as gravel (e.g., ballast, rocks, and/or the like) and may be used to support the rails  106 . 
         [0022]      FIG. 2  illustrates a more detailed view of the railroad chassis  104  of  FIG. 1 . In some embodiments, the railroad chassis  104  may include a wheeled car comprising a ballast supply  112 , a track lifting device (not shown), at least one source of compressed air  116  (e.g., air compressor), and a plurality of workheads  118 . The railroad chassis  104  also may include various framing elements (e.g., frame  111 ) for coupling with elements described herein, as well as an operator cab. 
         [0023]    In some embodiments, ballast stones may include crushed rock, gravel, and/or other small, hard particulate material. Ballast stones may be held in the ballast supply  112  (e.g., a containing device, a hopper, a bin, and/or the like) of the railroad chassis  104 . In some embodiments, the ballast supply  112  may include a dispenser and/or conveyor belt for transporting and/or distributing ballast stones to various workheads  118  of the railroad chassis  104 . In some embodiments, this dispenser and/or conveyor belt may be mechanized and/or controlled by a computing system. Additionally, the ballast supply  112  may include one or more sensors for determining an amount (e.g., a volume, a weight, and/or the like) of ballast stones remaining in the ballast supply  112  and/or an amount of ballast stones to be dispensed to (and/or dispensed by) one or more workheads  118 . In some embodiments, determining an amount of ballast stones remaining in the ballast supply  112  may initiate, by the computing system, generation of an automated request for refilling the ballast supply  112  with a predetermined amount of ballast stones. In other embodiments, determining an amount of ballast stones to be dispensed to one or more workheads  118  may be performed by the computing system and/or may occur in response to a measurement associated with the ballast bed  110  as described in more detail below. 
         [0024]    In an embodiment, and as shown in  FIG. 3 , each workhead  118  may be configured to disperse and/or distribute ballast stones through blowing tubes  120 . A lower end of each workhead  118  may comprise one or more blowing tubes  120 . The blowing tubes  120  may be arranged on a workhead  118  as a single blowing tube  120 , a pair of blowing tubes  120 , and/or any other arrangement of blowing tubes  120 . 
         [0025]    Each blowing tube  120  may comprise a vertically elongated opening through which ballast stone is distributed. For example, during operation, a blowing tube  120  may be lowered into the ballast bed  110  so that ballast stones may be blown (e.g., inserted and/or injected) into gaps (e.g., voids, cavities, and/or the like) in the ballast bed  110  beneath rail ties  108 . This insertion of ballast stones into the ballast bed  110  may raise the rail ties  108  to a desired height so as to stabilize the rail ties  108  and increase alignment of the rails  106 . 
         [0026]    Each blowing tube  120  may further be configured to be independently inserted into the ballast bed  110 . For example, each workhead  118  (and thus each blowing tube  120 ) may independently pivot, move, and/or traverse laterally relative to a rail  106  and/or a rail tie  108 . In this manner, ballast stones may be distributed in the ballast bed  110  at precise angles and/or locations. This is particularly advantageous at intricate track intersections and/or switches in the railroad track. 
         [0027]    Additionally, in some embodiments, a blowing tube  120  may be independently operable (e.g., movable, adjustable, and/or the like) relative to its associated workhead  118 . For example, the blowing tube  120  may be independently rotatable, angularly adjustable, and/or extendable relative to the workhead  118  to which it is coupled. In some embodiments, a housing may be coupled to a distal end of the workhead  118  to accommodate insertion of the blowing tube  120  into the housing. A motor, or other activation device may be provided in the housing for causing rotation of the blowing tube  120  relative to the workhead  118  based on instructions received from a computing system associated with the rail vehicle  102 . The housing may contain one or more thrust bearings that accommodate rotation of the blowing tube  120  and ensure that the motor does not receive the thrust. Further, an anti-rotational pin may be deployed to lock the blowing tube  120  in place once it rotates to the desired position. Of course, the aforementioned description of the rotation mechanism for the blowing tube  120  is merely exemplary, and other embodiments are contemplated so long as the blowing tube  120  is independently rotatable relative to the workhead  118 . 
         [0028]    In some embodiments, the blowing tubes  120  may be capable of rotating about a vertical axis specifically designed to match a curvature of one or more non-uniform rail locations, such as at a railroad frog track intersection (e.g., railroad frog  126  of  FIG. 7 ). By allowing the blowing tubes  120  to rotate about the vertical axis, the elongated opening in each blowing tube  120  that deposits the ballast may face a side of the rail  106  in order to deliver ballast stone under a rail tie  108  and/or another track section. In some embodiments, the blowing tubes  120  may be curved. 
         [0029]    During operation, the track lifting device may be utilized to lift a portion of the rails  106  and/or rail ties  108  so that ballast stones may be blown into the ballast bed  110  underlying the rail ties  108 . The track lifting device may lift the rail  106  and/or underlying rail ties  108  to a predetermined distance above of the ballast bed  110  so that a desired amount of ballast stones may be inserted underneath the lifted rail ties  108 . In some embodiments, the movements of the track lifting device may be controlled by the computing system as described herein. 
         [0030]    Also during operation, air from an air compressor  116  associated with the workhead  118  may be utilized to insert and/or inject ballast stones through the blowing tube  120  and into the ballast bed  110 . In some embodiments, each workhead  118  may include an air compressor  116 . In other embodiments, workheads  118  may share a common air compressor  116  and/or may comprise multiple air compressors  118 . The computing system may determine an amount of air to be blown into each workhead  118  and through the blowing tube  120  as described in more detail below. 
         [0031]    In an embodiment, and as depicted in  FIG. 5 , the railroad chassis  104  may further comprise one or more third point lifting arms  124  operable to enable the blowing of ballast stones under portions of railroad tracks that are not uniform, such as railroad switches and/or crossing panels of adjacent railroad tracks, railroad frog track intersections, and/or the like. For example, a third point lifting arm  124  may be configured to move a workhead  118 , and in turn, an associated blowing tube  120 , laterally relative to the railroad chassis  104 . In this manner, the workhead  118  and the associated blowing tube  120  may move outwardly from the railroad chassis  104  along the third point lifting arm  124  so that the blowing tube  120  may be lowered into the ballast bed  110  underneath a rail tie  108  of an adjacent rail  106  (e.g., a rail  106  adjacent to the rail  106  on which the railroad chassis  104  is positioned). 
         [0032]    The third point lifting arm  124  may extend outwardly from the railroad chassis  104  using a hydraulic system. The third point lifting arm  124  may also be foldable and/or pivotable in relation to the railroad chassis  104 . 
         [0033]    In some embodiments, the third point lifting arm  124  may be operated by a maintenance professional located inside the railroad chassis  104  and/or by a second maintenance professional located outside the railroad chassis  104 . The workhead  118  may be configured to move a predetermined distance along the third point lifting arm  124  so that the workhead  118  (and thus the blowing tube  120 ) is positioned as desired near a rail tie  108  of an adjacent rail  106  and/or track section. Movements of the third point lifting arm  124  and/or the workhead  118  along the third point lifting arm  124  may also be controlled by the computing system as described herein. 
         [0034]    In an embodiment, and as depicted in  FIG. 6 , the railroad chassis  104  may be utilized at a rail switch. As shown in  FIG. 6 , the blowing tube  120  may be deployed at an angle relative to the vertical axis of the rail  106 . Importantly, utilizing multiple workheads  118  on the railroad chassis  104  and/or third point lifting arms  124  as described above may enable a railroad maintenance crew to blow ballast stones under rail ties  108  of rails  106  at non-uniform locations and angles, thereby raising the rails  106  at locations previously unserviceable by standard stoneblowers. 
         [0035]    As shown in  FIG. 7 , a railroad frog  126  may include a railroad track structure that is used at an intersection of two running rails  106  to provide support for railcar wheels and passageways for wheel flanges, thus permitting wheels on either rail  106  to cross over the rails  106 . On a rail wheel, the flange may be the inside rim which projects below the tread. Each railroad frog  126  may have about fifteen rail ties  108  under the rails  106  of the railroad frog  126 , and as such, tamping equipment and current stoneblowers cannot adequately maintain a railroad line at the railroad frog  126  because of the non-uniform nature of the rails  106  at the railroad frog  126 . Advantageously, the disclosed improved stoneblower  100  is operable to blow ballast stones under rail ties  108  of the rails  106  of the railroad frog  126 , as well as many other non-uniform sections of rail  106 . 
         [0036]    In operation, each independent workhead  118  may work in a similar manner as the ballast stone depositing process  128  depicted in  FIG. 8 . In a first step, the railroad chassis  104  may move along the rails  106  to a desired position on a particular section of railroad track. While moving along the rails  106 , one or more sensors associated with the railroad chassis  104  may collect track profile data associated with the rails  106 . These sensors may measure a height, a width, an orientation, a shape, a contour, an angle, a condition, and/or other factors associated with the rails  106 . 
         [0037]    A track design computer (e.g., the computing system as described herein) associated with the railroad chassis  104  and in communication with the one or more sensors may generate a track profile of the rails  106  along the particular section of rail  106 . Based on the generated track profile, the computer system may calculate an amount of ballast stone required to be blown into the ballast bed  110  underneath one or more rail tie(s)  108  along the particular section of the rail  106  to achieve a desired or optimum track profile. 
         [0038]    The computing system may then, based on the determined amount of ballast stone to be blown into the ballast bed  110 , determine a height to which the rails  106  and/or the rail ties  108  need to be raised so that the determined amount of ballast stone may be blown underneath the rail ties  108 . The computing system may instruct the track lifting device to lift the rail(s)  106  to at least the predetermined height so that adequate space in the ballast bed  110  is present (e.g., see step  1  of  FIG. 8 ). 
         [0039]    The computing system may also, based on the determined amount of the ballast stone to be blown into the ballast bed  110 , determine an amount of ballast stone held in the ballast supply  112  to be distributed to the one or more workheads  118  for injection into the ballast bed  110 . The computing system may instruct the ballast supply  112  to distribute the determined amount of ballast stone to the one or more workheads  118 . In some embodiments, the determined amount of ballast stone may be distributed to the one or more workheads  118  according to the computer system instructions continuously during the stoneblowing process and/or at a time prior to stoneblowing. 
         [0040]    The computing system may further, based on the determined amount of the ballast stone to be blown into the ballast bed  110 , determine an amount of compressed air to be blown by the air compressor(s)  116  for injecting the determined amount of ballast stone into the ballast bed  110 . The computing system may instruct the air compressor(s)  116  to distribute the determined amount of compressed air stone to the one or more workheads  118  and/or the blowing tubes  120 . 
         [0041]    The computing system may additionally, based on the determined amount of the ballast stone to be blown into the ballast bed  110 , determine a position of the one or more workheads  118  for optimally blowing the ballast stones into desired locations in the ballast bed  110 . In this manner, the computing system may instruct various movements and/or adjustments of at least one of the one or more workheads  118 , the associated blowing tubes  120 , and the third point lifting arm  124  so that the workheads  118 , and importantly the blowing tubes, are accurately and independently positioned for dispensing the ballast stones into the ballast bed  110  as desired. For example, the one or more workheads  118  (and thus the associated blowing tubes  120 ) may be independently lowered (e.g., inserted) into the ballast bed  110  at a predetermined location along the rail  106  and at a calculated angle relative to the rail  106  and/or rail tie  108 . Once inserted into the ballast bed  110 , the blowing tubes  120  may be rotated and/or adjusted with respect to the workheads  118 . 
         [0042]    The computing system may then instruct the one or more workheads  118  to independently blow the determined amount of compressed air and ballast stone through the blowing tubes  120  so that it is injected into the ballast bed  110  at one or more desired locations (e.g., see step  2  of  FIG. 8 ). For example, ballast stones may be blown underneath the rail tie  108  associated with the lifted rail  106 , thereby accumulating new ballast stones in the ballast bed  110  under the rail(s)  106  and/or rail tie(s)  108  (e.g., see step  3  of  FIG. 8 ). 
         [0043]    Once the determined amount of ballast stones is injected into the ballast bed, the computer system may instruct the track lifting device to lower the rails  106  and/or the rail ties  108  so that the rail ties  108  rest on the ballast bed  110  (e.g., see step  4  of  FIG. 8 ). Because of the ballast stones being injected into the ballast bed  110  to raise the ballast bed  110 , the rail(s)  106  and/or rail tie(s)  108  may similarly be raised, thereby leveling the rails  106  to a desired height and/or alignment (e.g., track profile). The railroad chassis  104  may then move along to another section of the rails and repeat the aforementioned stoneblowing process. 
         [0044]    Advantageously, the improved stoneblower system  100  described herein may be especially helpful at locations where two rails merge or intersect, such as at a railroad frog  126  and/or other non-uniform sections of railroad tracks. In addition, by allowing each workhead  118  (and therefore each blowing tube  120 ) to move, pivot, and/or be inserted independently, the railroad maintenance crews may be enabled to blow ballast stones under non-uniform sections of rails  106 , such as at railroad frogs  126  and/or railroad crossings. By allowing maintenance crews to raise rail ties  108  supporting these non-uniform sections of rails  106  by executing the aforementioned stoneblowing process, railroad frogs  126  and other crossings may have extended lifespans. For example, the rail ties  106  of these crossings may be raised to uniform heights at these locations by adjusting the height of the underlying ballast bed  110 , thereby reducing the wear and tear on the rails  106 . 
         [0045]    Referring to  FIG. 9 , the computing system may take the form of a computer or data processing system  200  that includes a processor  220  configured to execute at least one program stored in memory  222  for the purposes of performing one or more of the processes disclosed herein. The processor  220  may be coupled to a communication interface  224  to receive remote sensing data as well as transmit instructions to receivers distributed throughout the rail vehicle  102  and/or chassis  104 . The processor  220  may also receive and transmit data via an input/output block  225 . In addition to storing instructions for the program, the memory may store preliminary, intermediate and final datasets involved in techniques that are described herein. Among its other features, the data processing system  200  may include a display interface  226  and a display  228  that displays the various data that is generated as described herein. It will be appreciated that the data processing system  200  shown in  FIG. 9  is merely exemplary in nature and is not limiting of the systems and methods described herein. 
         [0046]    While various embodiments in accordance with the disclosed principles have been described above, it should be understood that they have been presented by way of example only, and are not limiting. Thus, the breadth and scope of the invention(s) should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the claims and their equivalents issuing from this disclosure. Furthermore, the above advantages and features are provided in described embodiments, but shall not limit the application of such issued claims to processes and structures accomplishing any or all of the above advantages.