This patent application pertains generally to railroad rails support systems and more specifically to a plate that supports railroad rails on ties with spikes where the plate is formed with integral sleeves that extend downwardly, receive the spikes and protect the spikes from bending and breaking.
Steel tie plates and “cut” spikes or other types of spikes have been commonly used to fasten railway rails to wooden crossties since the late 1800s. A vital function of the spikes is to transfer lateral forces from the train wheels to the crossties (or ties) as a train runs over the rails. Over time, a deformation zone can be created in a wooden tie, forming cavities from the top surface of the tie partially along two opposite sides of the spike. Once these cavities are formed, as each wheel runs over a rail, in response to the lateral forces, the spike is free to flex back and forth, much like a flagpole in wind. This flexing causes cracks in the spike, typically about one to two inches beneath the top surface of the wooden tie. Eventually, as a result of fatigue, the spike breaks at the flexing point.
Broken spikes are difficult to detect visually even by professional railway track rail inspectors and have resulted in numerous train derailments all over the world, causing death and injuries, as well as extensive property damage and delays in train movements. As rail shipments of cargo increase, these derailments become increasingly unacceptable, especially if the cargo includes hazardous materials.
Additionally, water and foreign materials, such as dirt and sand, can get into the deformation zones causing damage to the ties, the plate and the spike, reducing the useful life of plates, ties and spikes and requiring more frequent replacements of these components. Thus, the overall maintenance costs of the respective rails is increased by the breakage of the spikes.
There have been many attempts to solve the problem of transferring lateral loads into wooden crossties. For example, plates have been made with ridges or other projections on their bottom surface. However, these approaches were not very successful because they resulted in crushed and damaged wood fibers, thereby reducing the useful life of the tie. In addition, the plates settled into the tie over time, requiring the spikes to be re-driven.
The present invention relates to a railway tie plate that includes rigid hollow cylinders or sleeves that house spikes and prevent the spikes from breaking and prevent the generation of deformation zones in wooden crossties. The present invention does not crush and damage the wood fibers of the ties and does not require frequent re-tightening of spikes, providing an improved long term solution to the problem described above.
The sleeves can be of any shape (e.g., round or square) and can be rigidly affixed to the tie plate by welding, press fitting, or other means. Alternatively, the sleeves can be made integral with the plate. The sleeve and the hole can be concentric. As the spike is driven into tie plate, the spike passes through the hollow sleeve and into the wooden crosstie, securing the tie plate to the tie. The sleeve transfers the bending moment of the spike into the tie plate. The inclusion of the sleeve also increases the bearing area for the transfer of lateral loads, a more uniform bearing stress over the bearing area, and decreased opportunity for water to infiltrate the bearing stress zone in the wood. As such, the plate also preserves wood fiber strength and lessens water-related degradation such as rust, decay, wood degradation and iron degradation.
The sleeve can include a bushing (e.g., plastic bushings) or a coating to further protect the wood fibers of the ties from wear and further increase the weight bearing area surrounding the spike.
In an embodiment, the present invention is directed to a plate assembly for supporting and attaching a rail on a tie using a spike that comprises a tie plate that has a hole for receiving and securing the spike, a clip that is arranged to secure the rail to the tie plate and a sleeve that is attached to the plate and extends downwardly from the plate when the plate is mounted on the tie. The sleeve is dimensioned to prevent lateral flexing of the spike after the spike has been inserted through the hole and the sleeve.
In an embodiment, the present invention is directed to a tie plate supporting a rail on a wood tie by a spike. The tie plate comprises a tie plate body that has a generally flat shape with a plate bottom surface and a sleeve that defines an orifice receiving the spike. The sleeve is sized and shaped to prevent deflection of the spike when the spike is inserted through the orifice and is imbedded in the wood tie.
The tie plate body can be formed with a hole and the sleeve can be sized and shaped to pass through the hole. The sleeve and tie can have matching cross-sectional shapes.
In an embodiment, the present invention is directed to a method of attaching a tie plate to a tie. The tie plate includes a generally flat bottom surface and a sleeve that extends from the bottom surface and defines an orifice. The method comprises the steps of attaching the tie plate to the tie with the sleeve extending into the tie and driving a spike through the hole until a portion of the spike is imbedded in the tie and securing the tie plate to the tie, with the sleeve being positioned to prevent lateral deflection of the spike. The sleeve can extend into tie by about 1 to 2 inches.
The tie can be predrilled form a hole in the tie receiving the sleeve. The bottom surface of the plate can have a plurality of sleeves arranged in a pattern and the tie can be predrilled to form a plurality of holes for receiving the sleeves, the holes being generated simultaneously. The plurality of sleeves can be arranged in a pattern, and the tie can be predrilled using a jig with a plurality of drill heads arranged in the pattern to predrill the tie with holes.
In an embodiment, the crosstie can be prepared for inclusion of the tie plate by using a plurality (e.g., four) rigid cylindrical drills ganged together to drill all required holes in a tie simultaneously. The tie plate can then pressed down on top of the tie with the sleeves being inserted through the holes formed in the tie. The plate can then be attached to the tie using straight and/or threaded spikes.
For threaded spikes a two-stage drill bit can be used that bores a staged hole starting from the top section that has a larger diameter for the sleeve and a lower section with a smaller diameter for the spike.
With reference now to the drawings, and in particular to
The first ridge 24 extends longitudinally about the plate 20 and delimits the channel 22 at a first side thereof. The second ridge 28 is spaced from the first ridge 24, extends longitudinally about the plate 20 and delimits the channel 22 at a second side thereof. The first clip 32 includes a first end portion 44 that is configured to be arranged partially within an opening 46 of the first shoulder 26 and a second end portion 48 that is configured to apply a retaining force on the first flange 17 of the rail 16. The second clip 34 includes a first end portion 50 that is configured to be arranged partially within an opening 52 of the second shoulder 30 and a second end portion 54 that is configured to apply a retaining force on the second flange 18 of the rail 16. The first holes 36 are configured to receive straight spikes 40 and the second holes 38 are configured to receive the threaded spikes 42. The spikes 40, 42, when inserted through the respective openings holes 36, 38 on the tie plate 20 and into the tie 14, secure the tie plate 20 to the tie 14.
The sleeves 160, 260, 360, 460, 462, 463 may be made of a variety of materials or combinations thereof. In an embodiment, the sleeves 160, 260, 360, 460, 462, 463 may be made from the same material as the tie plate, such as steel. In another embodiment, the sleeves 160, 260, 360, 460, 462, 463 can be made of a plastic material. In yet another embodiment, the sleeves 160, 162, 260, 262, 360, 362, 460, 462 can be coated with a protective plastic or an external member (e.g., metal, plastic, elastomeric, etc.) can be arranged over the exterior periphery of the sleeve 160, 260, 360, 460, 462, 463.
In an embodiment, the plate 120, 220, 320, 420 and sleeves 160, 260, 360, 460, 462, 463 associated therewith can be made in a single step by molding, casting, stamping or other similar process.
As shown in an embodiment in
As shown in an embodiment in
In another embodiment, the holes 136, 236, 336, 436, 438, 439, 536, 636 in the respective plates 120, 220, 320, 420, 520, 620 can have the same cross-sectional diameter and shape as the internal diameter of the respective sleeve 160, 260, 360, 460, 462, 463, 560, 660 and the sleeves 160, 260, 360, 460, 462, 463, 560, 660 can be attached to a bottom surface of the respective plate 120, 220, 320, 420, 520, 620.
Regardless of plate assembly 100-600 elected for use in conjunction with a tie, the tie must be properly prepared. More particularly, holes must be formed in the tie to accommodate the sleeves and spikes. These holes can be individually drilled using conventional means. Alternatively, a more efficient technique involves the use of multiple drills simultaneously. For example, in an embodiment, a jig 700 (see
The accompanying drawings illustrate embodiments of present invention and its respective constituent parts, however, other types and styles are possible, and the drawings are not intended to be limiting in that regard. Thus, although the description above and accompanying drawings contains much specificity, the details provided should not be construed as limiting the scope of the embodiment, but merely as providing illustrations of some of the features of the embodiment. The drawings and the description are not to be taken as restrictive on the scope of the embodiment and are understood as broad and general teachings in accordance with the present invention. While the present embodiment has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that modifications and variations to such embodiment, including, but not limited to, the substitutions of equivalent features, materials, or parts, and the reversal of various features thereof, may be practiced by those of ordinary skill in the art without departing from the spirit and scope of the invention.
This patent application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 62/379,848, filed Aug. 26, 2016, which is hereby incorporated by reference herein in its entirety as part of the present disclosure.
Number | Date | Country | |
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62379848 | Aug 2016 | US |