HIGH RESILIENT DIRECT FIXATION FASTENER IN STANDARD FOOTPRINT

Abstract

A bonded, direct fixation fastener as a supportive structure for a rail on a railroad bed comprising a top member or plate having a center portion having an upper face and a lower face; the top plate defining first and second wall sections each defining an outer perimeter having an outer face defining a lower face section and an upper face section; wherein a first angle between the lower face section and a horizontal surface of the railroad bed is lower than a second angle between the upper face section and the horizontal surface of the railroad bed; a bottom plate or member having first and second anchoring sides connected by first and second elements; wherein the bottom plate or member defines an opening; wherein the bottom plate has first and second wall members each having an interior face; and an elastomeric or rubber portion disposed between the top plate and the bottom plate.

Claims

1. A bonded, direct fixation fastener as a supportive structure for a rail on a railroad bed comprising: a top member or plate having a center portion having an upper face and a lower face; the top plate defining first and second wall sections each defining an outer perimeter having an outer face defining a lower face section and an upper face section; wherein a first angle between the lower face section and a horizontal surface of the railroad bed is lower than a second angle between the upper face section and the horizontal surface of the railroad bed; a bottom plate or member having first and second anchoring sides connected by first and second elements; wherein the bottom plate or member defines an opening; wherein the bottom plate has first and second wall members each having an interior face; and an elastomeric or rubber portion disposed between the top plate and the bottom plate.

2. The bonded, direct fixation fastener of claim 1 wherein, the upper face of the center portion is flat and defines a substantially rectangular or substantially square shape.

3. The bonded, direct fixation fastener of claim 1 wherein, the first angle is about 80 and the second angle is about 88.

4. The bonded, direct fixation fastener of claim 1 wherein, the bottom plate or member defines a substantially rectangular shape.

5. The bonded, direct fixation fastener of claim 1 wherein, an interior perimeter of the opening is defined by a plurality linear walls and two semi-circular walls each having a radius of curvature of about 1.75 inches.

6. The bonded, direct fixation fastener of claim 5 wherein, each of the two semi-circular walls has a radius of curvature of about 1.75 inches.

7. The bonded, direct fixation fastener of claim 1 wherein, the elastomeric or rubber portion disposed between the top plate and the bottom plate encapsulates all elements of the top plate except for the interior faces of open cylinders for attaching the bonded, direct fixation fastener to a railroad rail and the upper face of the center portion of the top plate and the bottom plate except for a bottom surface of the bottom plate and serrated surfaces around anchoring apertures defined by the bottom plate and the anchoring apertures.

8. The bonded, direct fixation fastener of claim 1 wherein, the lower face of the center portion defines first and second beveled edges; wherein each of the first and second beveled edges has an inner portion and an outer portion and wherein a first thickness of the rubber or elastomeric material between the outer portions and a top surface of the bottom plate is greater than a second thickness of the rubber or elastomeric material between the inner portions and the top surface of the bottom plate.

9. The bonded, direct fixation fastener of claim 8 wherein, the first thickness is about 0.85 inches and the second thickness is about 0.63 inches.

10. The bonded, direct fixation fastener of claim 1 wherein, a first thickness of the rubber or elastomeric material between the lower face section of the outer face of the top plate wall and the inner face of the bottom plate wall is less than a second thickness of the rubber or elastomeric material between the upper face section of the outer face of the top plate wall and the inner face of the bottom plate wall.

11. The bonded, direct fixation fastener of claim 10 wherein, the first thickness is about 0.88 inches and the second thickness is about 0.98 inches.

12. The bonded, direct fixation fastener of claim 1 wherein, the bonded, direct fixation fastener produces a vertical spring-rate in the range of about 45,000 lbf/in. to about 65,000 lbf/in.

13. The bonded, direct fixation fastener of claim 1 wherein, the top plate has a rail attachment means comprising open cylinders for attaching the bonded, direct fixation fastener to a railroad rail using a clip.

14. The bonded, direct fixation fastener of claim 1 wherein, each of the top plate and the bottom plate comprise one or more of the materials selected from the group of a metal, an alloy, cast steel and ductile iron.

15. The bonded, direct fixation fastener of claim 1 wherein, each of the top plate and the bottom plate comprises ductile iron grade 65-45-12.

16. The bonded, direct fixation fastener of claim 1 wherein, each of the first and second elements comprises a beam having a generally trapezoidal cross-section having at least one sharp corner and at least one round corner.

17. The bonded, direct fixation fastener of claim 5 wherein, the bottom plate defines a drainage channel from each of the semi-circular walls across the underside of each anchoring side.

18. The bonded, direct fixation fastener of claim 1 wherein, each of the anchoring sides defines an aperture surrounded by a serrated surface for use in attaching the bottom plate or member to a rail bed.

19. The bonded, direct fixation fastener of claim 1 wherein, each of the interior faces of the bottom plate is angled at about 75 with respect to horizontal.

20. The bonded, direct fixation fastener of claim 1 wherein, the elastomeric portion has a hardness in the range of 55 to 65 durometer A or Shore A.

21. The bonded, direct fixation fastener of claim 1 wherein, the elastomeric portion has a hardness of 60 durometer A or Shore A.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] For the present disclosure to be easily understood and readily practiced, the present disclosure will now be described for purposes of illustration and not limitation in connection with the following figures, wherein:

[0029] FIG. 1 is a top perspective view of a preferred embodiment of a bonded, direct fixation fastener of the present disclosure;

[0030] FIG. 2 is a bottom perspective view of the bonded, direct fixation fastener of FIG. 1;

[0031] FIG. 3 is another top perspective view of the bonded, direct fixation fastener of FIG. 1;

[0032] FIG. 4 is another bottom perspective view of the bonded, direct fixation fastener of FIG. 1;

[0033] FIG. 5 is a top plan view of the bonded, direct fixation fastener of FIG. 1;

[0034] FIG. 6 is a cross-sectional view of the bonded, direct fixation fastener of FIG. 5 along the Line A-A;

[0035] FIG. 7 is a side elevation view of the bonded, direct fixation fastener of FIG. 1;

[0036] FIG. 8 is a cross-sectional view of the bonded, direct fixation fastener of FIG. 7 along the Line B-B;

[0037] FIG. 9 is another top plan view of the bonded, direct fixation fastener of FIG. 1;

[0038] FIG. 10 is another side elevation view of the bonded, direct fixation fastener of FIG. 1;

[0039] FIG. 11 is yet another side elevation view of the bonded, direct fixation fastener of FIG. 1;

[0040] FIG. 12 is a field end elevation view of the bonded, direct fixation fastener of FIG. 1;

[0041] FIG. 13 is a gage end elevation view of the bonded, direct fixation fastener of FIG. 1;

[0042] FIG. 14 is a bottom plan view of the bonded, direct fixation fastener of FIG. 1;

[0043] FIG. 15 is another bottom plan view of the bonded, direct fixation fastener of FIG. 1;

[0044] FIG. 16 is a partial isometric side view of the bonded, direct fixation fastener of FIG. 1 showing preferred embodiments of the top plate and bottom plate thereof through a transparent representation of the elastomeric coating thereof;

[0045] FIG. 17 is a cross-sectional view of the bonded, direct fixation fastener of FIG. 7 along a centerline of the center portion of the top plate thereof;

[0046] FIG. 18 is a top plan view of a preferred embodiment of a bottom plate of the bonded, direct fixation fastener of FIG. 1;

[0047] FIG. 19 is a side elevation view of the bottom plate of FIG. 18;

[0048] FIG. 20 is an end elevation view of the bottom plate of FIG. 18;

[0049] FIG. 21 is a top perspective view of the bottom plate of FIG. 18;

[0050] FIG. 22 is a top perspective view of a preferred embodiment of a top plate of the bonded, direct fixation fastener of FIG. 1;

[0051] FIG. 23 is a side elevation view of the top plate of FIG. 22;

[0052] FIG. 24 is a top plan view of the top plate of FIG. 22; and

[0053] FIG. 25 is an end elevation view of the top plate of FIG. 22.

DETAILED DESCRIPTION

[0054] In the following detailed description, reference is made to the accompanying examples and figures that form a part hereof, and in which is shown, by way of illustration, specific embodiments in which the inventive subject matter may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice them, and it is to be understood that other embodiments may be utilized and that structural or logical changes may be made without departing from the scope of the inventive subject matter. Such embodiments of the inventive subject matter may be referred to, individually and/or collectively, herein by the term invention merely for convenience and without intending to voluntarily limit the scope of this application to any single disclosure or inventive concept if more than one is in fact disclosed.

[0055] The following description is, therefore, not to be taken in a limited sense, and the scope of the inventive subject matter is defined by the appended claims and their equivalents.

[0056] An illustrated preferred embodiment of the low vertical stiffness bonded direct fixation fastener (LVS BDFF) 10 of the present disclosure is shown in FIGS. 1-25. The LVS BDFF 10 comprises a top member or plate 12 having a generally horizontal rectangular or square flat center portion 13 having an upper face 7 and a lower face 9 having beveled edges 19. Top plate 12 has two wall sections 11 each defining an outer perimeter 14 having an outer face 15 defining a lower face section 16 and an upper face section 17. Preferably, as shown in FIGS. 6 and 16, lower face section 16 is angled at about 80 and defines an angle a with respect to vertical of about 10. Upper face section 17 is angled at about 88 and defines an angle b with respect to vertical of about 2. Top plate 12 has rail attachment means comprising open cylinders 18 for attaching the LVS BDFF 10 to a railroad rail (not shown) using a clip (not shown). More preferably, the clip may comprise a spring clip of a Pandrol design which is in standard use in the rail industry. As used herein, the term Low Vertical Stiffness (LVS) is synonymous with the term High Resilient as given in the title of the present application.

[0057] Top plate 12 and bottom plate 20 may be made of any durable metal or alloy and are preferably made of cast steel or ductile iron. More preferably, top plate 12 and bottom plate 20 are made from ductile iron grade 65-45-12.

[0058] As shown in FIGS. 14 and 18, a preferred embodiment of the LVS BDFF 10 of the present disclosure further comprises a substantially rectangular bottom plate or member 20 having anchoring sides 8 connected by beam elements 22 and defining opening 21. As shown in FIG. 17, beam elements 22 preferably have a generally trapezoidal cross-section having both sharp corners 34 and round corners 35.

[0059] An interior perimeter of opening 21 is defined by linear walls 23, 24, 25, 26, 27 and 28 and two semi-circular walls 31 each having a radius of curvature 32 of about 1.75 inches. Bottom plate 20 defines a drainage channel 56 from each of the semi-circular walls 31 across the underside of anchor portion 8 to allow any air, water or other fluid/liquid to drain or be expelled from inside of cavity 21A to the outside environment when the LVS BDFF 10 flexes under load. Preferably, bottom plate or member 20 is adapted to be attached to a rail bed (not shown). For such purpose, each anchoring side 8 preferably defines an aperture 54 surrounded by a serrated surface 55. Bottom plate or member 20 may be attached, using aperture 54, by any means used in the rail industry including spikes, screws, bolts, clips, spring clips, and bolt clamps.

[0060] As shown in FIGS. 6 and 16, bottom plate 20 has a pair of wall members 29 each having an interior face 30. Preferably, each interior face 30 is angled at about 75. Between top plate 12 and bottom plate 20 and encapsulating all elements of the top plate 12 and bottom plate 20 except for flat portion 13 of top plate 12 and serrated surfaces 55 of bottom plate 20 is an elastomeric portion 40. Elastomeric portion 40 preferably is of a hardness in the range of 55 to 65 durometer A or Shore A and more preferably it is 60 durometer A or Shore A. LVS BDFF 10 provides low stiffness in a standard footprint by having large opening 21 in bottom plate 20 with the unique geometry, shown in FIGS. 2, 4, 15, 18 and 21, minimizing vertical stiffness while maximizing the lateral bearing area against lateral loads, and using a rubber whose hardness is around 60A.

[0061] As shown in FIGS. 8 and 17, beveled edges 19 on lower face 9 of center portion 13 allow the thickness of the rubber or elastomeric material 40 between lower face 9 and the top surfaces of beam members 22 to increase preferably from about 0.63 at point c to about 0.85 at point d to lower the overall stiffness of the LVS BDFF 10.

[0062] As shown in FIGS. 6 and 16, the increase in angle from 80 of lower face 16 to 880 of upper face 17 allows the thickness of the rubber or elastomeric material 40 between outer face 15 of top plate wall 11 and the inner face 30 of bottom plate wall 29 to increase preferably from about 0.88 at point d1 to about 0.98 at point d2 to lower the overall stiffness of the LVS BDFF 10.

[0063] Preferably the LVS BDFF 10 of the present disclosure produces a vertical spring-rate in the range of about 55,000 lbf/in.

[0064] In the foregoing Detailed Description, various features are grouped together in a single embodiment to streamline the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the disclosure require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.