INTEGRATED TRAIN RAIL SYSTEM WITH TIES AND THERMAL EXPANSION JOINTS

Abstract

A railroad tie that is positioned on a rail bed as part of a rail system comprises a first end section, a second end section, and a middle section The middle section extends between and couples the first end section and the second end section The first end section has a first width The second end section has a second width The middle section has a middle width that is at least five percent different than the first width and the second width The middle width can be at least five percent less than the first width and the second width Additionally, the first width can be substantially equal to the second width Further, the middle section can extend away from the first end section at a first angle of between approximately 75 and 95 degrees

Description

BACKGROUND

Conventional train rail systems are comprised of six basic elements: (1) the steel rail; (2) the tie plate of “chair” that the rail sits on; (3) the railroad tie or “sleeper” to which two tie plates are affixed; (4) the fasteners that secure the rail to the tie plate and the railroad tie; (5) a joint system for adjoining consecutive lengths of rail sections; and (6) the foundation/bed of ballast rock within which the railroad ties rest and the track system is held in place.

Typical railroad ties are generally rectangular in shape and are generally laid transverse to the direction of the rails. Traditionally and most commonly, railroad ties are made of wood, although concrete, plastic and steel railroad ties are currently used as well.

Wood is the least expensive material used for the manufacturing of railroad ties, but it also has the shortest life cycle before needing replacement. For example, wooden railroad ties are more subject to weather related degradation, can be weakened due to insect attack, and are more likely to release the spike or screws that hold the rail to the tie plate. Additionally, the preservatives used to extend the life of the wood railroad ties can be an environmental contaminant.

Concrete railroad ties are considerably more expensive than wooden railroad ties and cannot be comingled with other types of railroad ties due to their weight and the different equipment required for handling and installation of the concrete railroad ties. Concrete railroad ties are also susceptible to stress cracking from the wheel loads moving across the railroad tie, do not absorb vibrations as well as other railroad ties, and do not attenuate the wheel to rail noise as well as other types of railroad ties. Further, concrete railroad ties can have accelerated failure due to incorrect cement recipes, insufficient curing time, and/or environmental degradation.

Plastic railroad ties are more expensive than wood and are not readily available in large quantities. Additionally, plastic railroad ties are more likely than concrete or wood to shift from side loads due to a lower coefficient of friction with the rock ballast.

Steel railroad ties typically last longer and are less susceptible to weather related degradation than wooden railroad ties. Additionally, steel railroad ties can absorb the thermal stresses, but the relatively lightweight steel ties utilized due to cost concerns results in steel tie systems that do not resist shifting of the rails from accumulated thermal loads. Moreover, steel railroad ties can cause grounding/electrical isolation problems for track signaling systems.

The predominant means for affixing consecutive sections of steel rail is butt-welding them together for a connected length being as much as a mile or longer. The single piece of welded rail is then installed onto the tie plates and railroad ties. Such continuous welded rail, or CWR, can be stronger than sectioned rail and can be less maintenance intensive. Typical steel rail is made from high quality hot rolled steel. Steel rail is subject to very high stress loads induced by the steel wheels of the train cars and environmental changes in the temperature. Accordingly, CWR faces certain intrinsic and serious problems that do not occur with sectioned rail that uses conventional expansion joints, in that they face significant thermal stresses as the steel used to make the rails expands in length when heated and contracts in length when cooled. Thus, the unsolved problem of thermal stress in CWR systems requires persistent, ongoing repair.

Thermally induced stress problems in the steel rails are a well recognized and well understood issue in the rail industry. Currently, expensive and elaborate expansion joints are sometimes used in the more vulnerable and valuable track sections of high-speed passenger lines, such as bridges and curves. Full resolution of the thermal stress problem can be accomplished by the frequent use of these types of expansion joints along the full length of track. However, doing so would greatly increase the costs of installing a rail system.

Therefore, a new rail system is needed that can have a relatively low installed cost; be significantly durable and weather resistant; successfully attenuate vibration and noise; allow for precise rail positioning; eliminate thermally induced stresses without a penalty in cost; not compromise rail strength at the section joints; be impervious to insect attack; eliminate environmental contamination from wood preservatives; greatly reduce track maintenance; increase operational performance; and increase passenger safety.

SUMMARY

The present invention is directed to a railroad tie that is positioned on a rail bed as part of a rail system. In certain embodiments, the railroad tie comprises a first end section, a second end section, and a middle section. The middle section extends between and couples the first end section and the second end section. The first end section has a first width. The second end section has a second width. Further, the middle section has a middle width that is at least five percent (5%) different than the first width and the second width.

In certain embodiments, the middle width is at least five percent (5%) less than the first width and the second width. In one such embodiment, the middle width is at least twenty-five percent (25%) less than the first width and the second width. Additionally, in one embodiment, the first width is substantially equal to the second width.

As a result of this design, (i) the first end section and the middle section cooperate to define a first pocket, and (ii) the second end section and the middle section cooperate to define a second pocket. In such embodiments, the pockets functions to inhibit relative movement between the railroad tie and the rail bed.

Further, in certain embodiments, the railroad tie is substantially Z-shaped. In such embodiments, the middle section extends away from the first end section at a first angle of between approximately seventy-five (75) and ninety-five (95) degrees. Still further, in one such embodiment, the middle section also extends away from the second end section at a second angle of between approximately seventy-five (75) and ninety-five (95) degrees.

Alternatively, in one embodiment, the railroad tie can be substantially dumbbell shaped. In such embodiment, the railroad tie further includes a first intermediate section and a second intermediate section. The first intermediate section is positioned between the first end section and the middle section. Additionally, the first intermediate section has a first intermediate width that is different than the first width and the middle width. Further, the second intermediate section is positioned between the second end section and the middle section. The second intermediate section has a second intermediate width that is different than the second width and the middle width.

In some embodiments, the railroad tie further includes a bottom surface and a top surface. In certain embodiments, the bottom surface has one or more cavities that each has an area at its opening that is at least approximately eighty (80) square millimeters. Further, the cavities can be substantially evenly spaced along the bottom surface. Additionally, in one such embodiment, the one or more cavities do not extend through the top surface.

Additionally, the present invention is directed to a rail system including a rail bed, a plurality of railroad ties that are positioned on the rail bed, and a pair of spaced apart rails that are coupled to the plurality of railroad ties. In some embodiments, the railroad ties have features as described above.

Still further, the present invention is directed to a rail joint for joining together a first rail section and a second rail section of a rail system that supports a rail vehicle, wherein the first rail section and the second rail section are positioned substantially along the same line. In certain embodiments, the rail joint comprises a first joint member and a second joint member. The second joint member is selectively coupled to the first joint member such that the second joint member at least partially overlaps the first joint member. In one embodiment, each joint member is designed to individually support the weight of the rail vehicle.

In certain embodiments, the first joint member is fixedly secured to the first rail section and the second joint member is fixedly secured to the second rail section.

Yet further, in some embodiments, the first joint member includes a first aperture and a first slot and the second joint member includes a second aperture and a second slot. In such embodiments, the rail joint further comprises a pair of connectors that extend through the first joint member and the second joint member to selectively couple the first joint member to the second joint member. For example, one connector can extend substantially through the first aperture and the second slot, and the other connector can extend substantially through the second aperture and the first slot. The connectors cooperate to allow relative translational movement between the first joint member and the second joint member.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:

FIG. 1 is a top view of an embodiment of a portion of a rail system having features of the present invention;

FIG. 2A is a top view of an embodiment of a railroad tie having features of the present invention;

FIG. 2B is a side view of the railroad tie illustrated in FIG. 2A;

FIG. 2C is a bottom view of the railroad tie illustrated in FIG. 2A;

FIG. 2D is a cross-sectional side view of the railroad tie taken along line 2D-2D in FIG. 2C;

FIG. 3 is a top view of another embodiment of a railroad tie having features of the present invention;

FIG. 4 is a top view of still another embodiment of a railroad tie having features of the present invention;

FIG. 5A is a top view of an embodiment of a half expansion joint having features of the present invention;

FIG. 5B is a side view of the half expansion joint illustrated in FIG. 5A;

FIG. 5C is a side view of the half expansion joint illustrated in FIG. 5A;

FIG. 5D is a cross-sectional end view of the half expansion joint cut along line 5D-5D in FIG. 5C;

FIG. 5E is a cross-sectional end view of the half expansion joint cut along line 5E-5E in FIG. 5C;

FIG. 5F is a cross-sectional end view of the half expansion joint cut along line 5F-5F in FIG. 5C;

FIG. 5G is cross-sectional top view of the half expansion joint cut along line 5G-5G in FIG. 5C;

FIG. 6A is a partially exploded top view of a rail expansion joint cut along line 5F-5F having features of the present invention, wherein the rail expansion joint is being positioned in a contracted configuration;

FIG. 6B is a top view of the rail expansion joint illustrated in FIG. 6A;

FIG. 6C is a cross-sectional top view cut along line 5G-5G of the rail expansion joint of FIG. 6B;

FIG. 6D is a partially exploded top view of the rail expansion joint cut along line 5G-5G illustrated in FIG. 6A, wherein the rail expansion joint is being positioned in an expanded configuration;

FIG. 6E is a top view of the rail expansion joint illustrated in FIG. 6D;

FIG. 6F is a cross-sectional top view cut along line 5G-5G of the rail expansion joint of FIG. 6E;

FIG. 7A is a top view of the rail expansion joint illustrated in FIG. 6A;

FIG. 7B is a cross-sectional end view of the rail expansion joint cut along line 7B-7B in FIG. 7A;

FIG. 7C is a cross-sectional end view of the rail expansion joint cut along line 7C-7C in FIG. 7A;

FIG. 7D is a cross-sectional end view of the rail expansion joint cut along line 7D-7D in FIG. 7A;

FIG. 7E is a cross-sectional end view of the rail expansion joint cut along line 7E-7E in FIG. 7A;

FIG. 7F is a cross-sectional end view of the rail expansion joint cut along line 7F-7F in FIG. 7A; and

FIG. 7G is a simplified top view of the rail expansion joint illustrated in FIG. 7A and a portion of a rail vehicle.

DESCRIPTION

FIG. 1 is a top view of an embodiment of a portion of a rail system 10 having features of the present invention. As illustrated, the rail system 10 includes a rail bed 12, a plurality of railroad ties 14 that are positioned on and/or within the rail bed 12, a first rail 16 and a spaced apart second rail 18 that are supported on the railroad ties 14, a plurality of tie plates 20 that couple the first rail 16 and the second rail 18 to the railroad ties 14, and one or more rail joints 22. As discussed in greater detail herein, the design of the various components of the rail system 10 can be varied to suit the specific design requirements of the rail system 10.

As an overview, the rail system 10 of the present invention includes various features that enable the production and operation of a rail system 10 that has a reduced cost, higher strength, greater system integrity, is longer lasting, is safer, performs better, and that eliminates the need for almost constant maintenance.

In one embodiment, the rail bed 12 is made up of a plurality of ballast rocks that cooperate with the railroad ties 14 to inhibit the rails 16, 18 from moving or shifting relative to a surface 24, e.g., the ground, upon which the rail system 10 is situated. The ballast rocks in the rail bed 12 (also referred to herein as the ballast rock bed) have a tendency to settle and subside over time due to use, weathering effects, thermally induced loads and lateral forces toward the center of a curve as trains go through. Maintenance of the ballast rock bed 12 and keeping up the edges of the ballast rock bed 12 on the outside of the ends of the railroad ties 14, i.e. maintaining the integrity and positioning of the ballast rocks that make up the rail bed 12, is vital to maintaining the integrity of the rail system 10. For example, when forces parallel to the length of the railroad ties 14 occur, it is the friction force due to the weight of the railroad ties 14 and the rails 16, 18 plus any resistance by the ballast rocks of the rail bed 12 outside the ends of the railroad ties 14 that prevent shifting of the rails 16, 18 relative to the surface 24. Stated another way, correcting subsidence of the ballast rock bed 12 along the edges of the rail bed 12 outside the ends of the railroad ties 14 and keeping the ballast rock bed 12 intact is an important maintenance function in order to preserve the integrity of the rail system 10.

As illustrated in FIG. 1, the railroad ties 14 are positioned on and/or within the rail bed 12. The railroad ties 14 (five of which are shown in FIG. 1) are substantially evenly spaced apart from each other within the rail bed 12 with a plurality of ballast rocks positioned around and between each of the railroad ties 14. As noted above, the railroad ties 14 and the ballast rocks of the rail bed 12 cooperate to inhibit the rails 16, 18 from moving or shifting relative to the surface 24 on which the rail system 10 is situated. Stated another way, the railroad ties 14 are uniquely designed to interact with the ballast rocks of the rail bed 12 so that the railroad ties 14 will not shift relative to the surface 24 due the forces that act upon the railroad ties 14 from the movement of trains along the rails 16, 18.

The rails 16, 18 are coupled to and are supported by the railroad ties 14 via the tie plates 20. In particular, in the embodiment illustrated in FIG. 1, there are two tie plates 20 secured to each railroad tie 14, with one tie plate 20 being secured to each railroad tie 14 near either end of the railroad tie 14. The rails 16, 18 are mounted on the railroad ties 14 via the tie plates 20 such that the first rail 16 is mounted near one end of the railroad tie 14 and the second rail 18 is mounted near the other end of the railroad tie 14.

The tie plates 20 are secured to the railroad ties 14 with one or more fasteners 26. Stated another way, the rail system 10 includes one or more fasteners 26 that are designed to secure the rails 16, 18 to each of the tie plates 20 and each of the railroad ties 14. As illustrated in this embodiment, each tie plate 20 can be secured to a single railroad tie 14 with four fasteners 26. Alternatively, each tie plate 20 can be secured to a single railroad tie 14 with more than four or less than four fasteners 26. In certain embodiments, the fasteners 26 are carriage bolts that have a smooth, semi-spherical head above a lower square shoulder. Alternatively, a different type of fastener 26 may also be used without altering the breadth and scope of the present invention.

The one or more rail joints 22 are designed to couple together adjacent sections of rail. In particular, FIG. 1 illustrates that the first rail 16 includes a first rail section 16A and a second rail section 16B that are positioned substantially along a single line, wherein the first rail section 16A and the second rail section 16B are selectively coupled together with a rail joint 22. Somewhat similarly, FIG. 1 illustrates that the second rail 18 includes a third rail section 18A and a fourth rail section 18B that are positioned substantially along a single line, wherein the third rail section 18A and the fourth rail section 18B are selectively coupled together with a rail joint 22. As an overview, the rail joints 22, as will be discussed in greater detail below, are uniquely designed to compensate for the possible thermal expansion of the rails 16, 18 while maintaining the integrity and safety of the rail system 10.

FIG. 2A is a top view of an embodiment of a railroad tie 214 having features of the present invention. The design of the railroad tie 214 can be varied to suit the particular requirements of the rail system 10 (illustrated in FIG. 1). In this embodiment, the railroad tie 214 has a shape that is similar to that of a narrow or tall “Z” shape, and the railroad tie 214 includes a first end section 228, a spaced apart second end section 230, and a middle section 232 that extends between and couples the first end section 228 and the second end section 230.

In this embodiment, the first end section 228 has a first width 228W and the second end section 230 has a second width 230W. As illustrated, the first width 228W and the second width 230W can be substantially equal. Alternatively, the railroad tie 214 can be designed so that the first width 228W is greater than or less than the second width 230W. Further, the middle section 232 has a middle width 232W that is different than the first width 228W and the second width 230W. In different embodiments, the middle width 232W can be 5%, 10%, 15%, 25%, 40%, 50% or some other percent different than the first width 228W and/or the second width 230W. As illustrated, the middle width 232W can be less than the first width 228W and the second width 230W. Alternatively, the middle width 232W can be greater than the first width 228W and/or greater than the second width 230W.

As illustrated in FIG. 2A, the first end section 228 is substantially rectangular in shape and includes a first side 228F, an opposed second side 228S that is substantially parallel to the first side 228F, an outer end 228O, and an opposed inner end 228I that is substantially parallel to the outer end 228O. Somewhat similarly, the second end section 230 is substantially rectangular in shape and includes a first side 230F, an opposed second side 230S that is substantially parallel to the first side 230F, an outer end 230O, and an opposed inner end 230I that is substantially parallel to the outer end 230O. Alternatively, the first end section 228 and the second end section 230 can be designed to have a different shape.

In this embodiment, each end section 228, 230 includes a plurality of fastener apertures 234 that are each adapted to receive one of the fasteners 26 (illustrated in FIG. 1) that are utilized to secure the tie plate 20 (illustrated in FIG. 1) to the railroad tie 214. In particular, as illustrated, each end section 228, 230 can include four fastener apertures 234 that are positioned in a substantially rectangular shaped orientation relative to each other so as to each receive one of the fasteners 26 that are utilized to secure the tie plate to the railroad tie 214. In certain alternative embodiments, the end sections 228, 230 can be designed to include more than four or less than four fastener apertures 234, the fastener apertures 234 can have a different orientation relative to each other, and/or the fastener apertures 234 can be positioned on a different part of the railroad tie 214.

As illustrated in FIG. 2A, the middle section 232 is substantially rectangular in shape and extends away from and between the inner end 228I of the first end section 228 and the inner end 230I of the second end section 230. In particular, in this embodiment, the middle section 232 extends away from the inner end 228I of the first end section 228 near the second side 228S of the first end section 228, and the middle section 232 extends away from the inner end 230I of the second end section 230 near the first side 230F of the second end section 230, so as to form the substantially narrow “Z” shape of the railroad tie 214.

In some embodiments, the middle section 232 extends away from the first end section 228 at a first angle 236 of between approximately 75 and 95 degrees, and the middle section 232 extends away from the second end section 230 at a second angle 238 of between approximately 75 and 95 degrees. In one such embodiment, the middle section 232 extends away from the first end section 228 at a first angle 236 of approximately 85 degrees, and the middle section 232 extends away from the second end section 230 at a second angle 238 of approximately 85 degrees. In alternative embodiments, the middle section 232 can have a different shape, the middle section 232 can be oriented differently relative to the first end section 228 and the second end section 230, and/or the middle section 232 can extend away from the first end section 228 and the second end section 230 at different positions. For example, the middle section 232 can extend away from the first end section 228 at a first angle 236 of less than 75 degrees or greater than 95 degrees, and the middle section 232 can extend away from the second end section 230 at a second angle 238 of less than 75 degrees or greater than 95 degrees. Further, the middle section 232 can extend away from the inner end 228I of the first end section 228 near the first side 228F of the first end section 228, and the middle section 232 can extend away from the inner end 230I of the second end section 230 near the second side 230S of the second end section 230, so as to form a reversed narrow “Z” shape of the railroad tie 214.

Additionally, as illustrated in FIG. 2A, the middle section 232 of the railroad tie 214 has a first vertical face 240 and an opposed second vertical face 242 that intersect respectively with the inner end 228I of the first end section 228 and the inner end 230I of the second end section 230 with curved surfaces. The “Z” shaped profile or footprint of the railroad tie 214 creates a first pocket 244 in the area where the inner end 228I of the first end section 228 meets with the first vertical face 240 of the middle section 232, and creates a second pocket 246 where the inner end 230I of the second end section 230 meets with the second vertical face 242 of the middle section 232. After the railroad ties 214 have been installed on the rail bed 12 (illustrated in FIG. 1) and ballast rocks have been filled in and around the assembled railroad ties 214 and up to a top surface 214T of the railroad ties 214, the first pocket 244 and the second pocket 246 provide a hook into and across the greater majority of the rail bed 12 in both directions perpendicular to the rails 16, 18 (illustrated in FIG. 1). These two pockets 244, 246 of each railroad tie 214 provide far superior grip into the ballast rocks of the rail bed 12 so as to inhibit relative movement or shifting between the railroad ties 214 and the rail bed 12 when or if side loads are introduced to the rail system 10.

In certain embodiments, the railroad tie 214 is a single, contiguous piece and not an assembly of numerous pieces. Alternatively, the first end section 228, the second end section 230 and the middle section 232 can be formed separately and subsequently fixedly secured together to form the completed railroad tie 214.

One method of manufacturing the railroad tie 214 would be conventional injection molding of the railroad tie 214 from virgin or recycled plastic. Another method of manufacturing the railroad tie 214 would be compression or ram-molding technique that would use a combination of finely ground plastic and sand as the material to be molded. In the compression or ram-molding technique a certain measure of the ground plastic would be uniformly mixed with an appropriate amount of conventional sand and then loaded within the lower cavity half of the mold pair. The upper mold half would be driven down and into the lower mold half with enough force to compress the sand and ground plastic mixture to create a cold flow of the plastic around the sand particles and binding them together. This process requires no added heat or cooling for the mixed plastic and sand or for the finished product. Similar compression or ram molding as described herein is known in other applications and results in a very tough finished product that is resistant to impact damage, equally capable of handling tension and compression loads as well as wood or plastic ties, resistant to weather damage, resistant to insect destruction, creates precision finished parts, quick to manufacture with no curing time required, long life cycle, does not generate any environmental contamination, can be fabricated from recycled or virgin plastics and has a lower anticipated cost than wood ties that have been treated with preservatives. Additional combinations of different materials can be used in the compression molding of the railroad ties 214 such as chipped ABS plastic from car bumpers, crumb rubber from tires and others. Still alternatively, another method can be utilized to fabricate the railroad tie 214 or other materials could be used without altering the breadth and scope of the present invention.

FIG. 2B is a side view of the railroad tie 214 illustrated in FIG. 2A. In particular, FIG. 2B illustrates that the railroad tie 214 is designed to have a substantially uniform thickness or height throughout the first end section 228, the second end section 230 and the middle section 232. Alternatively, the first end section 228, the second end section 230 and the middle section 232 can be designed so that one or more of the sections 228, 230, 232 have a different thickness than the other sections 228, 230, 232.

FIG. 2C is a bottom view of the railroad tie 214 illustrated in FIG. 2A. As illustrated in FIG. 2C, the railroad tie 214 further includes a bottom surface 214B having the plurality of fastener apertures 234 and one or more cavities 248.

As noted above, the plurality of fastener apertures 234 are each adapted to receive one of the fasteners 26 (illustrated in FIG. 1) that are utilized to secure the tie plate 20 (illustrated in FIG. 1) to the railroad tie 214. In particular, as illustrated, each end section 228, 230 can include four fastener apertures 234 that are positioned in a substantially rectangular shaped orientation relative to each other so as to each receive one of the fasteners 26 that are utilized to secure the tie plate to the railroad tie 214. In certain alternative embodiments, the end sections 228, 230 can be designed to include more than four or less than four fastener apertures 234, the fastener apertures 234 can have a different orientation relative to each other, and/or the fastener apertures 234 can be positioned on a different part of the railroad tie 214.

In the embodiment illustrated in FIG. 2C, the railroad tie 214 includes numerous cavities 248 that are substantially evenly spaced apart along the bottom surface 214B of the railroad tie 214. In certain embodiments, the cavities 248 are substantially circular shaped and can be at least approximately one centimeter or ten millimeters (0.39 inches) in diameter. Stated another way, in such embodiments, the cavities 248 can be at least approximately 0.80 square centimeters or eighty square millimeters. In particular, FIG. 2C illustrates that the railroad tie 214 can include 47 cavities 248 that are at least approximately one centimeter in diameter. In certain alternative embodiments, the railroad tie 214 can be designed to include more than or less than 47 cavities 248, the cavities 248 can be designed to have a different size or shape, and/or the cavities 248 can have a different positioning along the bottom surface 214B of the railroad tie 214. For example, the cavities 248 can have a diameter that is at least approximately 0.5 centimeters, 0.75 centimeters, 1.25 centimeters, 1.5 centimeters, 2 centimeters, or some other size. Further, the cavities 248 can be square shaped, rectangle shaped, hexagon shaped, octagon shaped, oval shaped, or some other shape. In an embodiment that includes numerous cavities 248 that are substantially square shaped, the openings to the cavities 248 can have sides that are approximately 0.9 centimeters or nine millimeters in length to result in the same approximate area at the opening, e.g., approximately eighty square millimeters, as the cavities 248 discussed above.

The intent of the cavities 248 is to reduce the total volume and weight of the railroad tie 214 for ease of manufacture, lower cost of manufacturing with less material, shorter cycle time, generate more consistent material thickness throughout the railroad tie 214, and provide slight recesses for grabbing on to the sharp edges and points of the ballast rocks of the rail bed 12 (illustrated in FIG. 1) upon which the bottom surface 214B of the railroad tie 214 rests when installed. Stated another way, the cavities 248 cooperate with the pockets 244, 246 (illustrated in FIG. 2A) of each railroad tie 214 to provide far superior grip into the ballast rocks of the rail bed 12 so as to inhibit relative movement or shifting between the railroad ties 214 and the rail bed 12 when or if side loads are introduced to the rail system 10 (illustrated in FIG. 1).

FIG. 2D is a cross-sectional side view of the railroad tie 214 cut along line 2D-2D in FIG. 2C. As illustrated in FIG. 2D, the fastener apertures 234 are designed to extend fully through the bottom surface 214B and the top surface 214T of the railroad tie 214. In particular, the fastener aperture 234 includes a cylindrical pathway 234A that extends away from the top surface 214T of the railroad tie 214, and a shorter, wider diameter cylindrical recess 234B that is positioned adjacent to the bottom surface 214B of the railroad tie 214. The cylindrical pathway 234A and the cylindrical recess 234B are substantially concentric with each other. The fastener apertures 234 are designed so that the shank of the fastener 234 (illustrated in FIG. 1), e.g., the carriage bolt, would pass though the cylindrical pathway 234A and into the cylindrical recess 234B. The overall length of the fastener 234 would be just less than the height of the railroad tie 214 plus the thickness of the tie plate 20 (illustrated in FIG. 1). The fastener 234 would include a threaded portion that would reside in the cylindrical recess 234B, which would have a sufficient diameter for a conventional threaded nut to be fastened onto the threaded portion of the fastener 234 with a conventional socket without interference. When assembled, no portion of the fasteners 234, i.e. not the carriage bolt or the threaded nut, would extend below the bottom surface 214B of the railroad tie 214.

Additionally, as illustrated in FIG. 2D, the cavities 248 can be substantially cylindrical shaped and can penetrate the bottom surface 214B of the railroad tie 214 for a distance somewhat less than the overall vertical height of the railroad tie 214. Stated another way, the cavities 248 do not extend through the top surface 214T of the railroad tie 214. In alternative, non-exclusive embodiments, the cavities 248 have a depth that is approximately 60, 70, 80, or 90 percent of the overall vertical height of the railroad tie 214.

FIG. 3 is a top view of another embodiment of a pair of railroad ties 314 having features of the present invention. This embodiment can provide similar functional benefits as described herein above for the railroad tie 214 illustrated in FIG. 2A. In this embodiment, the railroad ties 314 again include a first end section 328, a spaced apart second end section 330, and a middle section 332 that extends between and couples the first end section 328 and the second end section 330. Additionally, the railroad ties 314 can further include a first intermediate section 350 that is positioned substantially between the first end section 328 and the middle section 332, and a second intermediate section 352 that is positioned substantially between the second end section 330 and the middle section 332. As illustrated, the railroad ties 314 can have a shape that is somewhat similar to that of dumbbell weights.

In this embodiment, the first end section 328 has a first width 328W and the second end section 330 has a second width 330W. As illustrated, the first width 328W and the second width 330W can be substantially equal. Alternatively, the railroad tie 314 can be designed so that the first width 328W is greater than or less than the second width 330W. Further, the middle section 332 has a middle width 332W that is different than the first width 328W and the second width 330W. In different embodiments, the middle width 332W can be 5%, 10%, 15%, 25%, 40%, 50% or some other percent different than the first width 328W and/or the second width 330W. As illustrated, the middle width 332W can be less than the first width 328W and the second width 330W. Alternatively, the middle width 332W can be greater than the first width 328W and/or greater than the second width 330W.

Additionally, the first intermediate section 350 has a first intermediate width 350W that is different than the first width 328W and the middle width 332W, and the second intermediate section 352 has a second intermediate width 352W that is different than the second width 330W and the middle width 332W. As illustrated, the first intermediate width 350W can be less than the first width 328W and greater than the middle width 332W, and the second intermediate width 352W can be less than the second width 330W and greater than the middle width 332W. Alternatively, the first intermediate width 350W can be greater than the first width 328W and/or less than the middle width 332W, and the second intermediate width 352W can be greater than the second width 330W and/or less than the middle width 332W. Further, in this embodiment, the first intermediate width 350W and the second intermediate width 352W are substantially equal. In alternative embodiments, the first intermediate width 350W can be greater than or less than the second intermediate width 352W.

As illustrated in FIG. 3, the first end section 328 is substantially rectangular in shape, the second end section 330 is substantially rectangular in shape, the first intermediate section 350 is substantially rectangular in shape and extends substantially perpendicularly away from the first end section 328 toward the second end section 330 from a center of the first end section 328, the second intermediate section 352 is substantially rectangular in shape and extends substantially perpendicularly away from the second end section 330 toward the first end section 328 from a center of the second end section 330, and the middle section 332 is substantially rectangular in shape and extends substantially perpendicularly between the first intermediate section 350 and the second intermediate section 352 from a center of the first intermediate section 350 to a center of the second intermediate section 352. In alternative embodiments, the first end section 328, the second end section 330, the first intermediate section 350, the second intermediate section 352 and the middle section 332 can have different shapes, the sections 328, 330, 332, 350, 352 can be oriented differently relative to each other, and/or the sections 328, 330, 332, 350, 352 can extend away from each other at different positions.

Further, in this embodiment, the different sections 328, 330, 332, 350, 352 of the railroad tie 314 cooperate to form eight pockets 354 in order to provide far superior grip into the ballast rocks of the rail bed 12 (illustrated in FIG. 1) so as to inhibit relative movement or shifting between the railroad ties 314 and the rail bed 12 when or if side loads are introduced to the rail system 10 (illustrated in FIG. 1).

Although not shown herein, this railroad tie 314 could also include molded in cavities similar to the cavities 248 found in the railroad tie 214 illustrated in FIG. 2C.

In this embodiment, each tie plate 20 (illustrated in FIG. 1) is again secured to the railroad tie 314 with four fasteners 26 (illustrated in FIG. 1), which extend through the four fastener apertures 334 that are shown near either end of the railroad tie 314. In particular, two fastener apertures 334 are positioned within each end section 328, 330 and two fastener apertures 334 are positioned within each intermediate section 350, 352. Alternatively, each tie plate 20 can be secured to the railroad tie 314 with more than four or less than four fasteners 26, and/or the fastener apertures 334 that are adapted to receive the fasteners 26 can be positioned in different areas of the railroad tie 314.

FIG. 4 is a top view of still another embodiment of a pair of railroad ties 414 having features of the present invention. This embodiment can provide similar functional benefits as described herein above for the railroad tie 214 illustrated in FIG. 2A. As illustrated, the railroad ties 414 can have a shape that could be described as an erect or straight “Z” shape. In this embodiment, the railroad ties 414 again include a first end section 428, a spaced apart second end section 430, and a middle section 432 that extends between and couples the first end section 428 and the second end section 430.

In this embodiment, the first end section 428 has a first width 428W and the second end section 430 has a second width 430W. As illustrated, the first width 428W and the second width 430W can be substantially equal. Alternatively, the railroad tie 414 can be designed so that the first width 428W is greater than or less than the second width 430W. Further, the middle section 432 has a middle width 432W that is different than the first width 428W and the second width 430W. In different embodiments, the middle width 432W can be 5%, 10%, 15%, 25%, 40%, 50% or some other percent different than the first width 428W and/or the second width 430W. As illustrated, the middle width 432W can be less than the first width 428W and the second width 430W. Alternatively, the middle width 432W can be greater than the first width 428W and/or greater than the second width 430W.

As illustrated in FIG. 4, the first end section 428 is substantially rectangular in shape, the second end section 430 is substantially rectangular in shape, and the middle section 432 is substantially rectangular in shape and extends substantially perpendicularly between the first end section 428 and the second end section 430 from near a side of the first end section 428 to near a side of the second end section 430. In alternative embodiments, the first end section 428, the second end section 430, and the middle section 432 can have different shapes, the sections 428, 430, 432 can be oriented differently relative to each other, and/or the sections 428, 430, 432 can extend away from each other at different positions.

Further, in this embodiment, the different sections 428, 430, 432 of the railroad tie 414 cooperate to form two pockets 454 in order to provide far superior grip into the ballast rocks of the rail bed 12 (illustrated in FIG. 1) so as to inhibit relative movement or shifting between the railroad ties 414 and the rail bed 12 when or if side loads are introduced to the rail system 10 (illustrated in FIG. 1).

Although not shown herein, this railroad tie 414 could also include molded in cavities similar to the cavities 248 found in the railroad tie 214 illustrated in FIG. 2C.

In this embodiment, each tie plate 20 (illustrated in FIG. 1) is again secured to the railroad tie 414 with four fasteners 26 (illustrated in FIG. 1), which extend through the four fastener apertures 434 that are shown near either end of the railroad tie 414. In particular, two fastener apertures 434 are positioned within each end section 428, 430 and four fastener apertures 434 are positioned within the middle section 432 with two of the fastener apertures 434 being positioned near each end section 428, 430. Alternatively, each tie plate 20 can be secured to the railroad tie 414 with more than four or less than four fasteners 26, and/or the fastener apertures 434 that are adapted to receive the fasteners 26 can be positioned in different areas of the railroad tie 414.

FIG. 5A is a top view of an embodiment of a half expansion joint 522A having features of the present invention. The design of the half expansion joint 522A can be varied to suit the specific design of the rails 16, 18 (illustrated in FIG. 1) and to suit the specific requirements of the rail system 10 (illustrated in FIG. 1). In particular, the half expansion joint 522A is designed so that at least a portion of the half expansion joint 522A has a cross-sectional shape that matches the cross-sectional shape of the rails 16, 18 with which the half expansion joint 522A will be used.

Additionally, in use, and as will be discussed in detail below, the half expansion joint 522A is designed to be utilized with a second half expansion joint 622B (illustrated in FIG. 6A) that can be substantially identical in design in order to form a complete rail joint 622 (illustrated in FIG. 6A). For example, in joining together the first rail section 16A (illustrated in FIG. 1) and the second rail section (illustrated in FIG. 1) of the first rail 16, one of the half expansion joints 522A, 622B will be fixedly secured, e.g., via butt-welding, to the first rail section 16A and the other half expansion joint 522A, 622B will be fixedly secured to the second rail section 16B.

As an overview, the half expansion joint 522A is designed to have sufficient strength throughout its length to independently support the weight of a train or other rail vehicle as it moves over the rail joint 622, even in those portions of the rail joint 622 where the half expansion joints 522A, 622B do not overlap.

As shown in the embodiment illustrated in FIG. 5A, the half expansion joint 522A includes a first side 556, a second side 558, a first end 560, a second end 562, a front section 564 that extends away from the first end 560, an overlap section 566 that extends between the front section 564 and the second end 562, and a first vertical face 568 that defines part of the front section 564 and that forms a portion of the border between the front section 564 and the overlap section 566. Stated another way, the front section 564 extends from the first end 560 to the first vertical face 568, and the overlap section 566 extends from the first vertical face 568 to the second end 562.

As viewed from the top view, as illustrated in FIG. 5A, the first side 556 of the half expansion joint 522A is substantially linear along the entire length of the first side 556. In contrast, as viewed from the top view, the second side 558 includes a stepped portion that is formed by the first vertical face 568 such that the width of the overlap section 566 is approximately one-half the width of the front section 564.

FIG. 5B is a side view of the half expansion joint 522A illustrated in FIG. 5A. In particular, FIG. 5B illustrates certain features of the half expansion joint 522A as viewed from the first side 556 of the half expansion joint 522A. As illustrated in FIG. 5B, the half expansion joint 522A further includes a head 570, a foot 572, a second vertical face 574, a pair of joint apertures 576, and a pair of joint slots 578. In alternative embodiments, the half expansion joint 522A can include more or less than two joint apertures 576 and/or more or less than two joint slots 578.

During use, the head 570 of the half expansion joint 522A will cooperate with the top of the rails 16, 18 to form a substantially uniform surface along which the wheels of the train will ride. Additionally, the foot 572 of the half expansion joint 522A coincides with the bottom of the rails 16, 18 and is secured to the railroad ties 14 (illustrated in FIG. 1) in a similar manner as the rails 16, 18 are secured to the railroad ties 14.

As illustrated, the second vertical face 574 is positioned near the first end 560 of the half expansion joint 522A. The second vertical face 574 and the first vertical face 568 (illustrated in FIG. 5A) help to define the portions of the half expansion joint 522A where the cross-section of the half expansion joint 522A varies from the first end 560 to the second end 562.

In the embodiment illustrated in FIG. 5B, the pair of joint apertures 576 extend fully through the half expansion joint 522A from the first side 556 to the second side 558 (illustrated in FIG. 5C). In this embodiment, the joint apertures 576 are substantially circular in shape and are each adapted to receive a connector 680 (illustrated in FIG. 6A) in order to selectively couple the first half expansion joint 622A (illustrated in FIG. 6A) to the second half expansion joint 622B (illustrated in FIG. 6A). Alternatively, the joint apertures 576 can be designed to have a different shape.

Additionally, in the embodiment illustrated in FIG. 5B, the pair of joint slots 578 extend fully through the half expansion joint 522A from the first side 556 to the second side 558. In this embodiment, the joint slots 578 have ends that are substantially semi-circular in shape and that are substantially identical in diameter to the joint apertures 576. The joint slots 578 are also each adapted to receive a portion of the connector 680 in order to selectively couple the first half expansion joint 622A to the second half expansion joint 622B. Alternatively, the joint slots 578 can be designed so that the ends have a different shape.

FIG. 5C is a side view of the half expansion joint 522A illustrated in FIG. 5A. In particular, FIG. 5C illustrates certain features of the half expansion joint 522A as viewed from the second side 558 of the half expansion joint 522A. As viewed from the second side 558 of the half expansion joint 522A, the joint apertures 576 and the joint slots 578 are visible to demonstrate that the joint apertures 576 and the joint slots 578 do extend fully through the half expansion joint 522A from the first side 556 (illustrated in FIG. 5B) to the second side 558. Additionally, in FIG. 5C, both the first vertical face 568 and the second vertical face 574 are visible. Further, with the overlap section 566 extending from the first vertical face 568 to the second end 562, FIG. 5C illustrates that the joint apertures 576 and the joint slots 578 are all positioned within the overlap section 566 of the half expansion joint 522A.

In one non-exclusive embodiment, the half expansion joint 522A has three different cross-sections as one moves from the first end 560 to the second end 562 of the half expansion joint, as illustrated in FIGS. 5D-5F. In particular, FIG. 5D is a cross-sectional end view of the half expansion joint 522A cut along line 5D-5D in FIG. 5C; FIG. 5E is a cross-sectional end view of the half expansion joint 522A cut along line 5E-5E in FIG. 5C; and FIG. 5F is cross-sectional end view of the half expansion joint 522A cut along line 5F-5F in FIG. 5C.

FIG. 5D illustrates the first cross-section of the half-expansion joint 522A, which extends from the first end 560 (illustrated in FIG. 5C) to the second vertical face 574 (illustrated in FIG. 5C). The first cross-section, as illustrated in FIG. 5D, is designed to match the cross-sectional profile of the rail section 16A, 16B, 18A, 18B (illustrated in FIG. 1) to which the half expansion joint 522A is being fixedly secured in order to enable a smooth transition for the train as it travels from the rail section 16A, 16B, 18A, 18B to the half expansion joint 522A and/or from the half expansion joint 522A to the rail section 16A, 16B, 18A, 18B.

In the embodiment illustrated herein, the first cross-section includes the head 570, the foot 572 and a web 582 that extends between the head 570 and the foot 572. As shown, the foot 572 is somewhat wider than the head 570 and the web 582 is substantially narrower than both the head 570 and the foot 572. This first cross-section is a profile of a typical Vignoles or flat bottom rail.

FIG. 5E illustrates the second cross-section of the half expansion joint 522A, which extends from the second vertical face 574 (illustrated in FIG. 5C) to the first vertical face 568 (illustrated in FIG. 5C). In the second cross-section, the web portion is essentially eliminated, and the half expansion joint 522A maintains the same width from the head 570 all the way down to the foot 572. Stated another way, in the second cross-section, the vertical edges of the head 570 have been extended down to intersect with the foot 572 of the half expansion joint 522A. In particular, in the transition zone, the unique design of the half expansion joint 522A includes this second cross-section wherein the web portion has been fully extended to the outer edges of the head 570. This widened cross-section for the full rail height is sufficient for the half expansion joint 522A to carry fully loaded rail cars.

FIG. 5F illustrates the third cross-section of the half expansion joint 522A, which extends from the first vertical face 568 (illustrated in FIG. 5C) to the second end 562 (illustrated in FIG. 5C). As such, the third cross-section is present through the entire length of the overlap section 566 (illustrated in FIG. 5A) of the half expansion joint 522A. The third cross-section essentially encompasses the same profile as the second cross-section as found in FIG. 5E, but the profile has been vertically cut in half. Accordingly, in the third cross-section, the head 570 as it extends all the way down to the foot 572 has a width that is approximately one-half of the width of the head 570 in the second cross-section. Further, in the third cross-section, the foot 572 has a width that is approximately one-half of the width of the foot 572 in the second cross-section.

FIG. 5G is cross-sectional top view of the half expansion joint 522A cut along line 5G-5G in FIG. 5C. In particular, FIG. 5G illustrates the view of the half expansion joint 522A that has been cut through the vertical axis of the half expansion joint 522A and through the centers of the joint apertures 576 and the joint slots 578. This view also reveals that the second side 558 is substantially planar in the vertical direction as it extends from the top of the head 570 (illustrated in FIG. 5B) of the half expansion joint 522A all the way to the bottom surface of the foot 572 (illustrated in FIG. 5B) of the half expansion joint 522A.

It is anticipated that half expansion joint 522A would be cast or forged pieces from steel of a quality equal or superior to the steel rail to which it will be welded. Prior to welding to the steel rail section, it is anticipated that the vertical face of the second side 558 of the overlap section 566 and the horizontal interior surfaces of the joint aperture 576 and the joint slots 578 would be machined to precision tolerances to facilitate the interface or matching up with another half expansion joint that has been pre-welded to a different section of steel rail.

The half expansion joint 522A has a certain symmetrical shape and features such that two sections of steel rail, each with a half expansion joint 522A pre-welded to one end, can be interfaced in a co-planar relationship with each second side 558 of the overlap section 566 and about the common vertical and longitudinal centerlines of the steel rails.

FIG. 6A is a partially exploded top view of a rail expansion joint 622 cut along section line 5G-5G having features of the present invention, wherein the rail expansion joint is being positioned in a contracted configuration. In particular, FIG. 6A illustrates a first half expansion joint 622A and a second half expansion joint 622B (also referred to herein as joint members) that are being selectively and slidingly coupled together to form the rail expansion joint 622. As noted above, in this embodiment, the first half expansion joint 622A and the second half expansion joint 622B are substantially identical in design in order to form the complete rail expansion joint 622. Further, each of the half expansion joints 622A, 622B are substantially identical in design to the half expansion joint 522A described in detail above in relation to FIGS. 5A-5G. To complete the rail expansion joint 622, a coupling assembly 684 must be utilized that allows for the two half expansion joints 622A, 622B to slide relative to one another and still maintain the co-planar relationship of the second side 658 of the overlap section 666 of each of the joint members 622A, 622B.

As an overview, the rail expansion joint 622 of the present invention is uniquely designed such that the first joint member 622A can be selectively coupled to the second joint member 622B such that the first joint member 622A at least partially overlaps the second joint member 622B, i.e. the overlap section 666 of the first joint member 622A at least partially overlaps the overlap section 666 of the second joint member 622B in a co-planar fashion, wherein each joint member 622A, 622B is designed to individually support the weight of the train or other rail vehicle as it moves along the rail expansion joint 622.

Additionally, the joint members 622A, 622B can slide relative to each other from the contracted configuration, illustrated in FIGS. 6A-6C, to an expanded configuration, illustrated in FIGS. 6D-6F, or anywhere in between, as a means of compensating for the thermal expansion and contraction of the rail sections 16A, 16B, 18A, 18B (illustrated in FIG. 1) due to temperature changes in the surrounding environment. This unique design allows for the railcar wheel to smoothly transition from one section of rail to the next without having to bridge across a physical gap. With conventional expansion joints it is the vertical displacement cycle of the rail car steel wheels slightly dropping off the end of one rail and then being lifted up by the beginning of the next rail that causes damage to the wheel, introduces impact loads to the rails, joints, ties and rail bed and causes the clickity-clack aural signature.

As illustrated in FIG. 6A, the coupling assembly 684 includes the joint apertures 676 and joint slots 678 that are present in each of the half expansion joints 622A, 622B, and a plurality of connectors 680 that are adapted to extend through the joint apertures 676 and the joint slots 678. In certain embodiments, the connectors 680 can be conventional UNC screw type bolt fasteners that can be used to assemble the half expansion joints 622A, 622B into a fully functional rail expansion joint 622. In one such embodiment, each connector 680 would be a conventional threaded fastener with a hex head and a smooth or unthreaded portion known as the shank 680A and a threaded portion 680B. The length of the shank 680A away from the bottom of the hex head would a small amount more, estimated to be 0.013 centimeters (0.005 inches), than twice the through dimension of joint apertures 676 and joint slots 678 and never less than twice that same through dimension. The threaded portion 680B of the connectors 680 would have slightly smaller diameter than the shank 680A and be fully threaded up to where the shank 680A commences. In alternative embodiments, a different type of connector 680 can be used.

Additionally, each connector 680 can include a conventional nut 685 (only one is illustrated in FIG. 6A) and a flat washer (not shown) that would go over the threaded portion to engage to the bottom the shank 680A. The length of the threaded portion 680B would be somewhat longer than the height of the nut and the thickness of the washer.

In the embodiment illustrated in FIG. 6A, the coupling assembly 684 includes four connectors 680 for selectively and slidingly coupling the first joint member 622A to the second joint member 622B. Alternatively, the coupling assembly 684 can be designed to include more than four or less than four connectors 680. It should be noted that in certain embodiments, the connectors 680 are not fully tightened so that the expansion joints 622A and 622B can slide relative to each other.

After the rail expansion joint 622 has been assembled, it is anticipated that some means would be used to prevent the nut from backing off the threaded portion 680B and to thwart vandalism. Employing an orbital riveter on the back end of the threaded portion 680B would be such a means for preventing the nut from loosening due to vibration and prevent easy disassembly or vandalism.

To be positioned in the contracted configuration, illustrated in FIGS. 6A-6C, each of the connectors 680 extends through one of the joint apertures 676 and is lined up to extend through one of the joint slots 678 at a semi-circular end of the joint slot 678 such that the second end 662 of one joint member 622A, 6226 will be at its closest point to the first vertical face 668 of the other joint member 662A, 662B.

As a result of the symmetry of the half expansion joints 622A, 622B, each of the connectors 680 that extend through one of the joint apertures 676 will be in alignment with the end of the opposing joint slot 678 that allows the second end 662 of one joint member 622A, 622B to be at its closest point to the first vertical face 668 of the other joint member 662A, 662B.

When being installed, the gap distance between the first vertical face 668 of one joint member 622A, 622B and the second end 662 of the other joint member 622A, 662B in a fully assembled rail joint 622 is dependent upon the ambient temperature and the actual rail temperature. Additionally, the distance between rail expansion joints 622 is dependent upon the climatic zone in which the rail system is installed. The greater the expected temperature variation that the steel rail will see, the shorter the distance between the expansion joints 622. For the upper Central Plains of North America spacing in the range of 200 feet would be anticipated.

FIG. 6B is a top view of the rail expansion joint 622 illustrated in FIG. 6A. In FIG. 6B, the connectors 680 are fully positioned through the corresponding joint apertures 676 (illustrated more clearly in FIG. 6C) and joint slots 678 (illustrated more clearly in FIG. 6C) such that the second sides 658 of the overlapping sections 666 of the joint members 622A, 622B are in a co-planar relationship with each other with the rail expansion joint 622 in the contracted configuration.

FIG. 6C is cross-sectional top view cut along line 5G-5G as found in FIG. 5C of the rail expansion joint 622 illustrated in FIG. 6B. In particular, FIG. 6C illustrates a top view of the rail expansion joint 622 that has been cut through the joint apertures 676 and the joint slots 678 to more fully demonstrate the positioning of the connectors 680 through the joint apertures 676 and the joint slots 678.

FIG. 6D is a partially exploded top view cut along line 5G-5G as found in FIG. 5C of the rail expansion joint 622 illustrated in FIG. 6A, wherein the rail expansion joint is being positioned in an expanded configuration.

To be positioned in the expanded configuration, illustrated in FIGS. 6D-6F, each of the connectors 680 extends through one of the joint apertures 676 and is lined up to extend through one of the joint slots 678 at a semi-circular end of the joint slot 678 such that the second end 662 of one joint member 622A, 622B will be at its farthest point to the first vertical face 668 of the other joint member 662A, 662B.

As a result of the symmetry of the half expansion joints 622A, 622B, each of the connectors 680 that extend through one of the joint apertures 676 will be in alignment with the end of the opposing joint slot 678 that allows the second end 662 of one joint member 622A, 622B to be at its farthest point to the first vertical face 668 of the other joint member 662A, 6628.

FIG. 6E is a top view of the rail expansion joint 622 illustrated in FIG. 6D. In FIG. 6E, the connectors 680 are fully positioned through the corresponding joint apertures 676 (illustrated more clearly in FIG. 6F) and joint slots 678 (illustrated more clearly in FIG. 6F) such that the second sides 658 of the overlapping sections 666 of the joint members 622A, 622B are in a co-planar relationship with each other with the rail expansion joint 622 in the expanded configuration.

FIG. 6F is a cross-sectional top view of the rail expansion joint 622 illustrated in FIG. 6E. In particular, FIG. 6F illustrates a top view of the rail expansion joint 622 that has been cut through the joint apertures 676 and the joint slots 678 along line 5G-5G as found in FIG. 5C to more fully demonstrate the positioning of the connectors 680 through the joint apertures 676 and the joint slots 678.

FIG. 7A is a top view of the rail expansion joint 622 illustrated in FIG. 6A, wherein the first half expansion joint 622A and the second half expansion joint. 622B have been fully coupled together to form the assembled rail expansion joint 622. In particular, FIG. 7A illustrates that the rail expansion joint 622 includes a first end 786, a first gap 788, an overlap area 790, a second gap 792, and a second end 794. As will discussed in detail below, the rail expansion joint 622 has different cross-sections as one moves from the first end 786, past the first gap 788, the overlap area 790 and the second gap 792 to the second end 794.

As will be demonstrated herein below, the rail expansion joint 622 is designed such that each half expansion joint 622A, 622B is able to individually support the weight of a rail vehicle 796, a portion of which is illustrated in FIG. 7G.

FIG. 7B is a cross-sectional end view of the rail expansion joint 622 cut along line 7B-7B in FIG. 7A. In particular, FIG. 78 illustrates the cross-section of the rail expansion joint 622 near the first end 786 (illustrated in FIG. 7A) of the rail expansion joint 622. As shown, the rail expansion 622 has a cross-section near the first end 786 that is substantially identical to the cross-section of the rail section 16A, 16B, 18A, 18B (illustrated in FIG. 1) to which the rail expansion joint 622 is being secured.

The resistance to bending of the rail sections 16A, 16B, 18A, 18B between two consecutive railroad ties 14 (illustrated in FIG. 1) is dependent on the height, the shape and thickness of the head and the foot of the rail section 16A, 16B, 18A, 18B and the thickness of the web between the head and the foot. Assuming that the rail sections 16A, 16B, 18A, 18B to which the rail expansion joint 622 is secured has a substantially standard rail cross-section, the typical web thickness is approximately 1.27 centimeters (or 0.5 inches) and the typical head thickness is approximately seven centimeters (or 2.75 inches). Accordingly, the cross-section of the rail expansion joint 622 near the first end 786, as illustrated in FIG. 7B, has a web 782 thickness of approximately 1.27 centimeters (or 0.5 inches) and a head 770 thickness is approximately seven centimeters (or 2.75 inches). Therefore, the ability of the rail expansion joint 622 near the first end 786 to support the weight of the rail vehicle 796 and to resist bending is substantially similar to that of a typical rail section 16A, 16B, 18A, 18B.

FIG. 7C is a cross-sectional end view of the rail expansion joint cut along line 7C-7C in FIG. 7A. In particular, FIG. 7C illustrates the cross-section of the rail expansion joint 622 in the first gap 788 (illustrated in FIG. 7A), wherein a rail vehicle 796 (a portion of which is illustrated in FIG. 7G) riding along the rail sections 16A, 16B, 18A, 18B (illustrated in FIG. 1) and the rail expansion joint 622 will only be supported by the first half expansion joint 622A (illustrated in FIG. 7A).

The cross-section of the rail expansion joint 622 within the first gap 788 has a thickness from the head 770 downward of approximately one-half the thickness of a typical head, or approximately 3.5 centimeters (or 1.375 inches). As can be easily seen, the thickness of the rail expansion joint 622 within the first gap 788 is substantially greater than the thickness of the web of a typical rail. Accordingly, the ability of the rail expansion joint 622 within the first gap 788 to support the weight of the rail vehicle 796 and to resist bending is not any less than a typical rail section 16A, 16B, 18A, 18B.

FIG. 7D is a cross-sectional end view of the rail expansion joint cut along line 7D-7D in FIG. 7A. In particular, FIG. 7D illustrates the cross-section of the rail expansion joint 622 in the overlap area 790 (illustrated in FIG. 7A), wherein the rail vehicle 796 (a portion of which is illustrated in FIG. 7G) will be supported by both half expansion joints 622A, 622B (illustrated in FIG. 7A).

The cross-section of the rail expansion joint 622 within the overlap area 790 has a thickness from the head 770 downward of approximately the thickness of a typical head, or approximately seven centimeters (or 2.75 inches). As can be easily seen, the thickness of the rail expansion joint 622 within the overlap section 790 is substantially greater than the thickness of the web of a typical rail. Accordingly, the ability of the rail expansion joint 622 within the overlap section 790 to support the weight of the rail vehicle 796 and to resist bending is significantly increased as compared to a typical rail section 16A, 16B, 18A, 18B (illustrated in FIG. 1).

FIG. 7E is a cross-sectional end view of the rail expansion joint cut along line 7E-7E in FIG. 7A. In particular, FIG. 7E illustrates the cross-section of the rail expansion joint 622 in the second gap 792 (illustrated in FIG. 7A), wherein the rail vehicle 796 (a portion of which is illustrated in FIG. 7G) riding along the rail sections 16A, 16B, 18A, 18B (illustrated in FIG. 1) and the rail expansion joint 622 will only be supported by the second half expansion joint 622B (illustrated in FIG. 7A).

The cross-section of the rail expansion joint 622 within the second gap 792 has a thickness from the head 770 downward of approximately one-half the thickness of a typical head, or approximately 3.5 centimeters (or 1.375 inches). As can be easily seen, the thickness of the rail expansion joint 622 within the second gap 792 is substantially greater than the thickness of the web of a typical rail. Accordingly, the ability of the rail expansion joint 622 within the second gap 792 to support the weight of the rail vehicle 796 and to resist bending is not any less than a typical rail section 16A, 16B, 18A, 18B.

FIG. 7F is a cross-sectional end view of the rail expansion joint cut along line 7F-7F in FIG. 7A. In particular, FIG. 7F illustrates the cross-section of the rail expansion joint 622 near the second end 794 (illustrated in FIG. 7A) of the rail expansion joint 622. As shown, the rail expansion 622 has a cross-section near the second end 794 that is substantially identical to the cross-section of the rail section 16A, 16B, 18A, 18B (illustrated in FIG. 1) to which the rail expansion joint 622 is being secured.

Accordingly, the cross-section of the rail expansion joint 622 near the second end 794, as illustrated in FIG. 7F, has a web 782 thickness of approximately 1.27 centimeters (or 0.5 inches) and a head 770 thickness is approximately seven centimeters (or 2.75 inches), just as that of a typical rail section. Therefore, the ability of the rail expansion joint 622 near the second end 794 to support the weight of the rail vehicle 796 and to resist bending is substantially similar to that of a typical rail section 16A, 16B, 18A, 18B.

FIG. 7G is a simplified top view of the rail expansion joint 622 illustrated in FIG. 7A and a portion of the rail vehicle 796. In particular, FIG. 7G illustrates a wheel 796A (although illustrated as a rectangle the contact between the wheel and the rail is nominally a line across the top surface of the rail) of the rail vehicle 796 at different positions along the length of the rail expansion joint 622 from the first end 786 to the second end 794. Stated another way, FIG. 7G illustrates the surface contact area that the wheel 796A “sees” as it passes through the length of the rail expansion joint 622. As demonstrated, at no time is the wheel 796A unsupported as it passes through the rail expansion joint 622. In fact, as the wheel 796A passes along the length of the rail expansion joint 622, the wheel 796A is always and continuously supported as by at least one, if not both of the half expansion joints 622A, 622B (illustrated in FIG. 7A of the rail expansion joint 622.

Furthermore, referring back to FIG. 1, it should be noted that that there is a railroad tie 14 intentionally positioned underneath the center of the assembled rail joint 22 and the length of the rail joint 22 itself is such that the beginning of each half expansion joint has a railroad tie 14 underneath it as well. This spacial relationship between the railroad ties, the length of the half joints, the overlap portion and the anticipated amount of expansion/contraction per rail joint 22 is by design such that there is no reduction in rail strength as the rail car/wheel passes through the entire rail joint 22.

While a number of exemplary aspects and embodiments of a rail system 10 have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope.

Claims

1. A railroad tie that is positioned on a rail bed as part of a rail system, the railroad tie comprising;

a first end section having a first width;

a spaced apart second end section having a second width; and

a middle section that extends between and that couples the first end section and the second end section, the middle section having a middle width that is at least five percent different than the first width and the second width,

2. The railroad tie of claim 1 wherein the middle Width is at least five percent less than the first width and the second width.

3. The railroad tie of claim 1 wherein the middle width is at least twenty-five percent less than the first width and the second width.

4. The railroad tie of claim 1 wherein the first width is substantially equal to the second width.

5. The railroad tie of claim 1 further comprising a bottom surface having one or more cavities that are at least approximately eighty square millimeters in area.

6. The railroad tie of claim 5 further comprising a top surface, wherein the one or more cavities do not extend through the top surface.

7. The railroad tie of claim 1 that is substantially Z-shaped

8. The railroad tie of claim 1 that is substantially dumbbell shaped.

9. The railroad tie of claim 1 wherein the middle section extends away from the first end section at a first angle of between approximately seventy-five and ninety-five degrees, and wherein the middle section extends away from the second end section at a second angle of between approximately seventy-five and ninety-five degrees.

10. The railroad tie of claim 1 wherein the first end section and the middle section cooperate to define a first pocket and the second end section and the middle section cooperate to define a second pocket, and wherein the first pocket and the second pocket inhibit relative movement between the railroad tie and the rail bed.

11. The railroad tie of claim 1 further comprising a first intermediate section that is positioned between the first end section and the middle section and a second intermediate section that is positioned between the second end section and the middle section, and wherein the first intermediate section has a first intermediate width that is different than the first width and the middle width, and wherein the second intermediate section has a second intermediate width that is different than the second width and the middle width.

12. A rail system comprising:

a rail bed:

a plurality of railroad ties that are positioned on the rail bed, the railroad ties having features as described in claim 1; and

a pair of spaced apart rails that are coupled to the plurality of railroad ties.

13. A railroad tie that is positioned on a rail bed as part of a rail system, the railroad tie comprising:

a top surface; and

a bottom surface having a plurality of cavities, wherein at least one of the cavities has an area at an opening to the cavity that is at least approximately eighty square millimeters, wherein the plurality of cavities do not extend through the top surface.

14. The railroad tie of claim 13 wherein the cavities are substantially evenly spaced along the bottom surface.

15. The railroad tie of claim 13 further comprising a first end section, a spaced apart second end section, and a middle section that extends between and that couples the first end section and the second end section, the middle section cooperating with the first end section to form a first pocket and cooperating with the second end section to form a second pocket, wherein the first pocket and the second pocket inhibit relative movement between the railroad tie and the rail bed.

16. The railroad tie of claim 15 wherein the middle section extends away from the first end section at a first angle of between approximately seventy-five and ninety-five degrees, and wherein the middle section extends away from the second end section at a second angle of between approximately seventy-five and ninety-five degrees.

17. The railroad tie of claim 15 wherein the first end section has a first width, the second end section has a second width and the middle section has a middle width that is at least five percent less than the first width and the second width.

18. A rail system comprising:

a rail bed;

a plurality of railroad ties that are positioned on the rail bed, the railroad ties having features as described in claim and

a pair of spaced apart rails that are coupled to the plurality of railroad ties.

19. A rail joint for joining together a first rail section and a second rail section of a rail system that supports a rail vehicle, the first rail section and the second rail section being positioned substantially along the same line, the rail joint comprising;

a first joint member;

a second joint member that is selectively coupled to the first joint member such that the second joint member at least partially overlaps the first joint member, wherein each joint member is designed to individually support the weight of the rail vehicle.

20. The rail joint of claim 19 wherein the first joint member is fixedly secured to the first rail section and the second joint member is fixedly secured to the second rail section.

21. The rail joint of claim 19 wherein the first joint member includes a first aperture and a first slot and the second joint member includes a second aperture and a second slot, and further comprising a pair of connectors that extend through the first joint member and the second joint member to selectively couple the first joint member to the second joint member, wherein one connector extends substantially through the first aperture and the second slot, and the other connector extends substantially through the second aperture and the first slot.

22. The rail joint of claim 21 wherein the connectors cooperate to allow relative translational movement between the first joint member and the second joint member.

23. The rail joint of claim 21 wherein the apertures are substantially circular in shape and the slots have ends that are substantially semi-circular in shape, and wherein the diameter of the apertures is substantially equal to the diameter of the ends of the slots.

24. A rail system comprising:

a first rail that includes a first rail section and a second rail section that is positioned substantially along the same line as the first rail section;

a second rail that is spaced apart from the first rail; and

a rail joint that is positioned substantially between the first rail section and the second rail section and that couples the first rail section to the second rail section, the rail joint having features as described in claim 19.

25. The rail system of claim 24 wherein the second rail includes a third rail section and a fourth rail section that is positioned substantially along the same line as the third rail section, and further comprising a second rail joint that is positioned substantially between the third rail section and the fourth rail section and that couples the third rail section to the fourth rail section, the second rail joint having features as described in claim 19.