Hollow Switch Tie Assembly for Railway

This application claims the benefit of priority to: U.S. Provisional No. 63/632,922 entitled “HOLLOW SWITCH TIE ASSEMBLY FOR RAILWAY,” filed on Apr. 11, 2024.

All the aforementioned applications are hereby incorporated by reference in their entirety.

Railway tracks operate using a number of switches to route rolling stock. Typically, a switch point is moved via a switch machine that is located at or near the railway track. A switch machine is generally configured to use mechanical force via a plurality of rods that, in turn, move the switch point. These rods are positioned between railway ties (or sleepers) in many circumstances. Other mechanical parts may be similarly disposed between the railway ties in order to support switching operations supported by switch machines.

However, there are problems with having switch machine components positioned between railway ties. Commonly, maintenance equipment is used to perform maintenance on tracks. For example, tamping machines physically move ballast to align railway ties and rails. But the exposed switch component can interfere with such operations, causing damage to the switch machine rods (and even the tamping equipment itself). Therefore, human personnel are often used for these sensitive sections, thus introducing human error, additional costs, and even safety issues.

Second, exposed switch components are exposed to environmental and mechanical hazards. These effects greatly reduce the duty cycle of mechanical components and increase maintenance costs. Further, such conditions lead to failures that may lead to loss of property and even life.

To address the aforementioned problems, hollow switch ties may be used. However, many problems reside within hollow switch ties that shall be disclosed herein. What is needed is a hollow switch tie that is configurable for various rail and/or switch configurations in order to improve maintenance, decrease installation time, enhance safety, and many other benefits.

A solution is disclosed that comprises a hollow switch tie assembly and a kit. A hollow switch tie assembly may be configured to be operatively connected to a plurality of rails, wherein the hollow switch tie assembly comprises a shell configured to be operatively connected to a plurality of support plates, wherein the plurality of support plates is configured to be operatively connected to a plurality of interface plates, wherein the plurality of interface plates is configured to be operatively connected to the plurality of rails, wherein the plurality of interface plates comprises a first interface plate and a second interface plate, wherein the first interface plate comprises a first rail base support configured to be operatively connected to a first rail within the plurality of rails, wherein the second interface plate comprises a second rail base support configured to be operatively connected to a second rail within the plurality of rails.

The plurality of support plates is operatively connected to the shell via a first plurality of fasteners, wherein the first plurality of fasteners is semi-permanent. The plurality of interface plates is operatively connected to the shell via a second plurality of fasteners, wherein the second plurality of fasteners is removable. The first rail base support and the second rail base support are configured with different angular orientations, respectively. The plurality of interface plates and the plurality of support plates have an H-shape. The shell comprises a first plurality of areas being configured to accommodate one or more heating components, wherein the shell further comprises a second plurality of areas that provides elastic support for the plurality of support plates.

The hollow switch tie assembly further comprises a second plurality of support plates operatively connected to the shell, wherein the second plurality of support plates is rectangular. The hollow switch tie assembly further comprises a plurality of roller assemblies operatively connected to the second plurality of support plates. The hollow switch tie assembly further comprises a first plurality of shims being metallic and non-electrically insulating. The hollow switch tie assembly further comprises a second plurality of shims being non-metallic and electrically insulating the plurality of support plates from the shell. The hollow switch tie assembly further comprises a cover plate and a plurality of cover plate fasteners operatively connecting the cover plate to the shell.

Various aspects will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. References made to particular examples and implementations are for illustrative purposes, and are not intended to limit the scope of the claims.

Various types of hollow switch ties are available in the industry. However, existing solutions have many issues that are addressed by the disclosed solution. Each of the problems with these existing offerings shall be discussed and addressed by the advantages of the disclosed solution.

One problem with existing solutions is the hollow switch tie is configured to be disposed at a straight section of track. Stated differently, existing solutions lack the capability to be placed in a curved section of track. This limitation is particularly problematic at or near switch machines, since the very nature of the switch is to direct rolling stock to a divergent path (having a curve).

Existing straight-track solutions are limited by the variety of rail fasteners compatible with the hollow switch tie. Rail fasteners are primarily responsible for creating cant, gauge, alignment, etc. These existing solutions are only compatible with rail fasteners that are substantially parallel to the direction of travel. As such, any significant adjustment to the rail geometry is limited.

In contrast, the disclosed solution is configured to be disposed at both straight and curved sections of track. To enable this functionality, the disclosed solution provides for operative connection of configurable rail fasteners. Configurable support enables the rail fasteners to be adjusted for curves. Additionally, the configurable support provides support for varying gauges, rail size (i.e., base width), cant, etc. In short, the disclosed solution offers at least, if not more, functionality compared to existing railway ties that currently support curved sections of track.

Some existing solutions are not configured to house switch machine components—commonly the switch machine rods. These types of solutions are simply designed to allow objects to pass under the rail (via the hollow tie). For instance, these types of hollow ties allow for the passing of cabling, pipes, conduit, etc. from one side of the track to the other. For example, signaling cable within conduit could be passed under the rails via a hollow switch tie. To state plainly, these types of solutions are only slightly better than providing a steel pipe under a traditional rail—or simply burying these types of components below the tie.

In contrast, the disclosed solution is configured to accept many types of railway components beyond those simply passing under a rail. Nevertheless, the disclosed solution may be used to pass conduit, cabling, piping, etc. from one side of the rail to the other (e.g., from field side to field side). The disclosed solution enables far more functionality. For example, the disclosed solution is particularly configured to accept switch machine components such as switch rods. Further, the disclosed solution is configured to be tightly coupled to existing switch machines in order to enable this functionality. One of skill in the art will appreciate that a simple hollow tie (as exists today) cannot provide such advanced functionality as that supported by the disclosed solution.

Many existing solutions relating to hollow ties are simply extensions to a switch machine. As stated, switch machines rely on components that span below the rails in order to move a switch point (or another element of track). In many cases, these near-rail components are exposed and simply disposed near the ballast. However, some solutions provide for a switch machine that relies on a fully integrated hollow tie. Essentially, the hollow tie and the switch machine are one device.

By having the switch machine and hollow tie completely integrated, the operator loses the flexibility in replacing one component. For example, a replacement of the switch machine requires a replacement of the hollow tie (and vice versa). Failures aside, operators may simply desire to upgrade a switch machine without replacing the hollow tie. However, combined solutions lack this flexibility and thus lead to unnecessary replacement of additional components.

In contrast, the disclosed solution provides a stand-alone, yet completely interoperable solution, in one aspect. The hollow switch tie assembly may be installed as a standalone component with or without a switch machine. Stated differently, the hollow switch tie assembly may be simply used as a channel for cabling, conduit, piping, etc. Additionally, the hollow switch tie assembly may be used with a switch machine in order to enclose switch machine components (e.g., switch rods). Note, the hollow switch tie assembly is configured to be interoperable with many types and makes of switch machines. In short, the disclosed solution may be used in service to legacy installations or as part of a new installation-one having various types of switch machines operatively connected.

Another problem with existing solutions relates to the use of insulating layers. Hollow ties are generally made of metal (usually ferromagnetic). As such, electrical currents will conduct through the tie. In general, the tie should not conduct electrical current for a number of reasons. The primary reason is due to interference with electrical signals traveling along the rail. Each individual rail carries a low voltage signal that is used for communication. When the two rails share current, this signal is interrupted. This problem is unique to metal-based ties since many lumber ties and concrete ties are not conductive.

Therefore, metal ties are insulated such that each rail is electrically isolated. Insulating layers are provided at various points in the tie and rail fastener. In general, these layers perform the intended function properly. However, during maintenance, especially replacement, these layers become easily damaged. Often, the layers are made from non-metallic materials that are not robust. As such, any movement or change can lead to degradation of the insulation which, as stated, can lead to electrical interference for rail-based signaling systems.

In contrast, the disclosed solution provides electrical insulation between each rail such that these sensitive electrical signals are protected from interference. The hollow steel tie assembly comprises a plurality of shims which can be installed at one time without the need for ongoing removal when components are serviced. For example, when the rail fastener and/or interface plate is replaced/serviced, the insulating layer can be left in position and thus protected from inadvertent damage during other maintenance operations. The plurality of shims is fixed in position, in part, with a plurality of support plates that provides support for other components of the solution. In short, the hollow steel tie assembly provides electrical insulation with high durability thus reducing maintenance costs as well as avoiding failure of electrical insulation requirements.

Another problem that affects existing solutions is the inability to address changes in track-related customization. Deployments in rail are complex. Many components are required to address many configurations. Track-related customization often requires custom work to be performed on components. For example, a switch machine may be deployed at a turnout with a particular geometry and handedness. If either requirement changes (as is often the case), then the hollow tie is often removed, altered, and reinstalled. Since tracks are essentially long sequences of interoperable parts, several parts of trackwork must be sent back for changes. In short, necessary changes are often impossible in the field.

Customizations, in short, cause many delays in deployment. Further, the costs increase. Additionally, safety may be compromised since any change has the risk of introducing errors. For example, a rushed customization order may inadvertently result in out-of-tolerance components being deployed.

In contrast, the disclosed solution is readily customizable. To achieve customization, the disclosed solution uses a plurality of interface plates that are operatively connected to the rail. These interface plates may address many types of changes to track configuration. For example, a first plurality of interface plates may be configured for a straight segment of track having a first gauge. If the straight segment now requires a slight curve with a slightly different gauge, then the first plurality of interface plates may be removed. A second plurality of interface plates may be configured (or preconfigured) to the slight curve and slightly different gauge. Next, the second plurality of interface plates may then be installed in place of the first plurality of interface plates.

One can conceive of a myriad of interface plates that are uniquely configured to almost any type of deployment. The interface plates may address any handedness, curve, gauge, cant, rail size (e.g., base width), material type, durability, strength, hardness, etc. These various interface plates may simply be installed into an already-installed disclosed hollow steel tie without excessive changes to the installation. Given that the installation of a hollow steel tie is non-trivial, personnel need not be concerned with removing an entire hollow tie to make somewhat minor changes to the connection between the hollow tie and the rail itself. This streamlining of installation and maintenance not only reduces costs but enhances safety for not only personnel but for passengers.

Another problem with existing hollow ties is the shape of the shell that houses the components. Some configurations of hollow ties rely on top plates that interface with a shell. To support the top plates, many shells have support flanges that are disposed inward. This configuration may provide support but causes the access to the internal components to be very difficult. For instance, personnel servicing a switch rod may have difficult accessing the components since the supporting flanges directly block access. For minor operations such as lubrication, this issue is not as problematic. However, significant servicing may require invasive operations to access components, including disassembly of the switch machine and/or hollow tie.

In contrast, the disclosed solution provides for outward-facing support flanges. As stated, the shell generally supports top plates. In the disclosed solution, the flanges of the shell are configured such that personnel can readily access the components housed in the shell without the need for invasive removal/disassembly of components. This configuration is made possible by the unique shape of the shell that is structurally configured to provide necessary support for top plates, rail fasteners, rail, etc.—without requiring the support flanges to cover the interior of the shell (and associated components).

Another problem with existing solutions relates to adding heating components to the interior of the hollow tie. Railways are subject to extreme operating conditions. Snow and ice are particularly problematic because switch machine components will freeze and become inoperative in cold conditions. To address this problem, some operators rely on heating components disposed at or near the switch machine and/or hollow tie. However, existing solutions provide suboptimal support for heating components. Many existing hollow ties rely on rectangular shell designs which do not provide additional space for heating components. Stated differently, existing solutions are designed only to support switch machine components-with heating components being an afterthought.

In contrast, the disclosed solution relies on a shell that is configured such that heating components can fit adjacent to switch machine components (e.g., switch rods). This functionality is provided by the unique shape of the shell which has a ventral bulge which enables heating components to be situated near the switch rods. As such, the disclosed solution is particularly useful in deployments where the existing hollow ties cannot support heating components. As stated above, the disclosed solution is configured to replace hollow ties without necessarily requiring replacement of the switch machine.

is a planar view of a hollow switch tie assembly, as shown from a top perspective. A plurality of axes is shown as a first axisX, a second axisY, and a third axisZ. The axisX is perpendicular to the direction of rolling stock traveling along the track. The axisY is parallel to the direction of travel of rolling stock moving along the track. The axisZ is vertical, as formed by the normal vector of the axesX,Y.

The hollow switch tie assemblyneed not only be used for switch machines. The hollow switch tie assemblyis generally operable to be used for the purpose of housing any type of equipment and/or components. For example, the hollow switch tie assemblymay be used to convey cabling from one side of a track to the other. Again, the benefit of the hollow switch tie assemblyis to provide a protective housing for railway equipment of any kind, whether moveable or static (such as electrical conduit, drain pipes, etc.).

While operable for other purposes, the hollow switch tie assemblyis generally configured to accommodate the components of a switch machine (or a railroad switch) that is disposed at or near a railway track. Switch machines typically rely on a number of “switch machine components” to move a switch point from a first position to a second position—examples of which include cabling, rods, screws, cantilevers, and any other means of physically pushing and/or pulling a switch point. The term “switch machine components” will be used throughout this disclosure to refer to the aforementioned components; however, one of skill in the art will appreciate that switch machine components may be those beyond the components enumerated above (e.g., tie-heating components, housings, sensors, etc.). Often, these switch machine components are disposed between the railway ties (i.e., in the cribs). However, the hollow switch tie assemblyis configured to accept and protect these switch machine components on both the field side and gauge side of the track.

The hollow switch tie assemblycomprises a shell, a plurality of support platesZ, a plurality of interface platesZ, a plurality of support platesZ, and a cover plate. The shellis generally configured to provide a cavity for the switch machine components. Further, the shellprovides for the support for the rail. Therefore, the shellis intended to be installed on ballast, in one aspect.

The plurality of support platesZ comprises a first support plateA and a second support plateB. In one aspect, the support platesA,B are generally configured in an H-shape in order to provide structural integrity to the shellas well as any rail interfacing plates disposed on the dorsal surface of the hollow switch tie assembly. Therefore, the plurality of support platesZ is substantially flat on the dorsal and ventral surfaces. In another aspect, the support platesA,B may not have the H-shape and instead be configured as separated strips on each side of the shell(for a total of four or more strips in total). In general, the plurality of support platesZ is configured to provide a substantially flat surface above the shell, which may otherwise not have a full bearing surface.

The plurality of interface platesZ comprises a first interface plateA and a second interface plateB. The interface platesA,B are configured to be installed on the dorsal surfaces of the plurality of support platesZ. The plurality of interface platesZ is configured to accommodate the fixation of a rail to the hollow switch tie assembly. As with the support platesA,B, the interface platesA,B have an H-shape.

The H-shapes of the plurality of support platesZ and the plurality of interface platesZ provides multiple benefits. First, the H-shapes provide for access to the interior of the shellsuch that switch machine components (e.g., switch rods) may be accessed. For example, the H-shape allows for the inspection and replacement of switch machine components without the need to physically remove any operatively connected rail. Second, the H-shapes enable movement of switch rod clips that are operatively connected to the switch point. For example, a switch rod may be disposed within the shellthat causes the switch point (and switch rod clip) to move (parallel to the axisX) between the H-shape. Stated simply, the H-shapes enable both movement of parts outside and within the shell. One of skill in the art will appreciate that cover plates may be installed above the H-shape to enclose the switch machine components, if so desired.

The plurality of interface platesZ comprises a plurality of rail fastenersZ. The plurality of rail fastenersZ comprises a first rail fastenerAA, a second rail fastenerAB, a third rail fastenerBA, and a fourth rail fastenerBB. The rail fastenersAA,AB are disposed on the dorsal surface of the interface plateA. Similarly, the rail fastenersBA,BB are disposed on the dorsal surface of the interface plateB.

The plurality of rail fastenersZ is generally configured to operatively connect a plurality of rails to the hollow switch tie assembly. The plurality of rails (not shown) is intended to be installed in a direction that is substantially parallel to the axisY. One of skill in the art will appreciate that the plurality of rail fastenersZ may require additional hardware (not shown) in order to operatively connect a rail. Such additional hardware includes tension clamps, bolts, screws, nuts, clips, etc. Given that the interface platesA,B may be removable, different types of rail fasteners may be employed for any given interface plate. As such, the interface plateA may have different rail fasteners than the interface plateB.

One of skill in the art will appreciate that several factors determine the design of a turnout, including (but not limited to): rail type, rail gauge, switch machine orientation, position within a turnout, any hand, any switch geometry, a type of switch machine, etc.-all of which shall be termed “switch design factors” throughout this disclosure. Traditionally, railway ties are installed by excavation of ballast. The railway tie is moved through the newly created trench/void. Next, ballast is replaced to support the railway tie under the rail. Then, crews affix the rail to the railway tie. One of skill in the art will appreciate that reciprocal operations relate to the removal of the railway tie. When the railway tie is not customizable, any change to switch design factors may lead to an entire change of the railway tie.

A non-customizable railway tie may require substantial changes before being installed (or reinstalled). For example, if the switch design factors change, a non-customizable railway tie may need to be sent back to a factory for updates since such changes are difficult in the field. These changes incur cost as well as delay. If the non-customizable railway tie cannot be changed/updated, the railway tie may need to be destroyed. The problem is further magnified when one considers that several railway ties are involved in any given segment of track.

In sharp contrast, the disclosed solution addresses these problems by providing a substantially customizable railway tie, namely the hollow switch tie assembly. The plurality of interface platesZ provides for a customizable interface between the hollow switch tie assemblyand the rail. One advantage of the plurality of interface platesZ is to address the switch design factors without the need to completely reconfigure (redesign) or entirely replace the hollow switch tie assemblyto address any one of those switch design factors. In other words, the plurality of interface platesZ may be coupled and/or decoupled from the hollow switch tie assemblyin order to accommodate a rail type, a rail gauge, a switch machine orientation, a position within a turnout, a type of switch machine, any hand, etc.

Therefore, the hollow switch tie assemblyis configurable, via at least the plurality of interface platesZ, for any type of rail installation while still providing enclosure of switch machine components. When a switch machine factor changes, the operator may simply obtain new interface plates to address the changed switch machine factor. For instance, assume an operator orders a hollow switch tie assemblyhaving a first plurality of interface plates that is configured for a left-hand turnout. Assume further the operator discovers that an environmental factor (e.g., poor soil, water, etc.) causes the turnout design to be changed to a right-hand turnout. The operator may simply change the first plurality of interface plates (for left-hand turnout) to a second plurality of interface plates (for right-hand turnout) without the need to replace the hollow switch tie assembly. Rather, the hollow switch tie assemblymay stay substantially the same when the plurality of interface plates is changed out for right-hand turnout.

The plurality of support platesZ comprises a first support plateA and a second support plateB. The plurality of support platesZ is generally configured to accommodate a plurality of roller assembliesZ (not visible).

The cover plateis disposed on the dorsal surfaces of the plurality of support platesZ. The cover plateis generally configured to provide protection of the switch machine components and prevent foreign objects from entering the shell. Foreign objects include ballast, foliage, animals, moisture, ice, debris, mechanical parts, etc. When the hollow switch tie assemblyis used for switch machines, the plurality of roller assembliesZ is likewise protected, in part, by the cover plate. While the cover plateis the only one shown, one of skill in the art will appreciate that cover plates may be installed at any position necessary to provide the benefits stated above. For example, a cover plate may be installed within the H-shapes of the plurality of support platesZ and/or the plurality of interface platesZ.

is a planar view of the hollow switch tie assembly, as shown from a front perspective. The instant view better shows the plurality of rail fastenersZ. Further, a segment is disposed slightly below the dorsal surface of the plurality of interface platesZ in order to accommodate a rail. In one aspect, the segment may be level wherein the rail sits flush on the dorsal surface of the plurality of interface platesZ. The cover plateis shown as being operatively connected to the shellusing a number of fastening components (e.g., bolts, cotter pins, etc.). One of skill in the art will note that the cover platemay be removed since the associated hardware is removable.

As will be shown later in more detail, the plurality of support platesZ is operatively connected to the shellvia semi-permanent fasteners. Semi-permanent fasteners include Huck bolts, Huck nuts, hot rivets, lock bolt fasteners, etc. With respect to the interface platesA,B, removeable nut-bolt configurations are used in order to remove the interface platesA,B. By having removable interface platesA,B, the hollow switch tie assemblymay be used and even reused for any type of switch machine factors.

is a perspective view of the hollow switch tie assembly, as shown from a top perspective. The instant view shows the semi-permanent fastening of the support platesA,B and the removable fastening of the interface platesA,B.

is a planar view of the hollow switch tie assembly, as shown from a front, exploded perspective. The hollow switch tie assemblyfurther comprises a first plurality of shimsZ and a second plurality of shimsZ.

The first plurality of shimsZ comprises a first shimAA, a second shimAB (not shown), a third shimBA, and a fourth shimBB (not shown). The shimsAA,AB are operatively connected to the ventral surface of the support plateA. The shimsBA,BB are operatively connected to the ventral surface of the support plateB. The plurality of shimsZ may be metallic or non-metallic. Further, the plurality of shimsZ may provide electrical insulation.