US3515347A

US3515347A - Rail fastenings

Info

Publication number: US3515347A
Application number: US718389A
Authority: US
Inventors: John Murray Waters; John Lucas; Gwyn Tudor Davis
Original assignee: Tempered Spring Co Ltd
Current assignee: Tempered Spring Co Ltd
Priority date: 1968-04-03
Filing date: 1968-04-03
Publication date: 1970-06-02
Anticipated expiration: 1987-06-02

Description

J. M. WATERS ETAL 3,515,347

June 2, 1970 RAIL FASTENINGS 3 Sheets-Sheet 1 Filed April 5, 1968 June 2, 1970 J. W TE ET AL 3,515,347

RAIL FASTENINGS Filed April 5, 1968 3 Sheets-Sheet :1

FIG.2.

June 2, 1970 M, WATERS ET AL 3,515,347

RAIL FASTENINGS FIG. 3 a

Filed April I5, 1968 United States Patent 3,515,347 RAIL FASTENINGS John Murray Waters and John Lucas, Allestree, and Gwyn Tudor Davis, Sheffield, England, assignors to The Tempered Spring Company Limited, Sheflield, England, a company of Great Britain and Northern Ireland Filed Apr. 3, 1968, Ser. No. 718,389 Int. Cl. E01b 9/48 US. Cl. 238-310 16 Claims ABSTRACT OF THE DISCLOSURE The invention is concerned with a rail fastening. This comprises, in combination with a tie (in this specification called a sleeper) or other rail foundation, a clip bearing on the rail flange, a shoulder on the rail foundation constituting an abutment for the flange, and a spacer disposed between the flange and the shoulder so that the flange abuts against the shoulder through the intermediary of the spacer. The shoulder and the spacer are of such shape that at least part of the contact area between them, as seen in horizontal section, describes an arc of a circle. This enables misalignment of the rail foundation with respect to the rail to be accommodated without any need for large clearances. Moreover, wedging action of the spacer on the rail resists creep or longitudinal rail movement.

This invention relates to rail fastenings, that is to say means for securing rails to sleepers or other rail foundations, particularly foundations of concrete or other cast or moulded materials. The invention is concerned with rail fastenings in which a clip bears on the rail flange and the flange abuts against an abutment through the intermediary of a spacer (usually made of insulating material). In known installations, angular misalignment of the rail foundation with respect to the rail and indeed creep or longitudinal rail movement present difliculties and the object of the invention is to provide an improved rail fastening which reduces at least some of those difliculties.

Accordingly, the invention provides a rail fastening comprising, in combination wtih a sleeper or other rail foundation, a clip bearing on the rail flange, a shoulder on the rail foundation constituting an abutment for the flange, and a spacer disposed between the flange and the shoulder so that the flange abuts against the shoulder through the intermediary of the spacer, the shoulder and the spacer being of such shape that at least part of the contact area between them, as seen in horizontal section, describes an arc of a circle. This circular arc portion is able to accommodate misalignment of the rail foundation with respect to the rail without having to provide large clearances moreover it resists creep or longitudinal rail movement by virtue of the wedging action in either direction of the spacer on the rail. Preferably the clip also bears upon the rail flange through the intermediary of the spacer. Preferably, the circular arc portion of the contact area slopes towards the centre of the circular arc so as to form a conical surface, and the spacer is wedge shaped as seen in vertical section. This facilitates insertion and removal of the spacer and helps to position the rail flange centrally in course of installation.

Preferably at the ends of the said circular arc portion the shoulder and the spacer gradually diverge from each other in order to prevent bad spots at the ends of the contact area. This may be accomplished by shaping the spacer and/or shoulder so that the circular arc portion merges smoothly into a different curve.

In order to improve the resilience of the space and Patented June 2, 1970 ice to permit its easier bedding on the shoulder, a small amount of relief may be given to the spacer where it engages the side edge of the rail flange and over that part of its extension lengthwise of the rail which provides the said contact area with the shoulder..

Alternatively or additionally the resilience of the spacer may be improved by forming it as a honeycomb or open cell structure.

The clip may be in the form of a spring plate and the rail fastening may comprise a reaction piece fixed in the foundation, the reaction piece consisting of a cross bar and two non-conjoined depending legs together constituting an upright hoop located substantially in one plane, with its cross bar spaced above the surface of the foundation and away from the rail flange, and a back support mounted on the said foundation on the side of the said cross bar remote from the rail, the clip bearing at one end on the flange and at the other end on the back support and fitting intermediately of its ends, within the said hoop, where it reacts substantially in the said plane against the said cross bar. A reaction piece consisting of a cross bar and two non-conjoined depending legs provides a hoop which avoids the difficulty encountered when using reaction pieces in the nature of a hoop in conjunction with some designs of concrete sleepers having reinforcing wires or bars or having cavities in the concrete. Preferably the reaction piece is made from bar metal of constant cross section. The legs may be shaped, for example by being corrugated, to assist anchorage in the foundation.

The said rail foundation may be a concrete sleeper and the shoulder thereof may be reinforced or modified to increase its tensile strength, impact resistance and resistance to spalling by inclusion of metallic or nonmetallic fiber reinforcement and/or by use of concrete modified by synthetic resins or other plastics or rubber or bitumen material. The fibre reinforcement may be cast in a first phase of the production of the sleeper, the second phase being the addition of orthodox concrete materials. A plate of for example steel, nylon or glassfibre may be embedded in the sleeper to reinforce the shoulder.

An embodiment of the invention and modifications thereof will now be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is an elevational view of the rail fastening arrangement, the cut-away left-hand rail fastening being shown in central section,

FIG. 2 is a plan view of FIG. 1, but showing only the right-hand rail fastening in position,

FIG. 3 is a section on the line IIIIII in FIG. 1, and

FIG. 4 is a sectional view of a modified form of sleeper with a hoop forming part of a rail fastening embedded therein.

Referring now to the drawings, the rail fastening for fastening a rail 1 to a concrete sleeper 2 comprises a clip 3 in the form of a spring plate, a reaction piece 4 fixed in the sleeper and comprising an upright hoop located substantially in one plane with its cross-bar 5 spaced above the sleeper 2 and away from the flap 6 of the rail 1 and a back support 7 mounted upon the sleeper on the side of the cross-bar 5 remote from the rail 1. The clip 3 bears at one end on the rail flange 6 through a spacer in the form of an insulator 11 made from nylon and at the other end on the back support 7 and fits, intermediately of its ends, within the hoop 4 Where it reacts substantially in the aforesaid plane against the cross-bar 5.

Lateral abutment for the rail 1,. which rests on a pad 8 of for example rubber, is provided by a shoulder 9, formed on the sleeper 2, through a dependent portion 10 of the insulator 11. The insulator 11 as seen in plan view (FIG. 2) is generally of U-shape with an upstanding flange 12 around its inner edge. The fork ends of the clip 3 bear on the limbs of the insulator 11 and are constrained against undue movement relatively to the insulator 11 by the flange 12.

The shoulder 9 and the dependent portion 10 of the insulator 11 where they are in contact describe, in horizontal section and also in plan view (see FIG. 2), circular arcs of the same radius. Moreover the shoulder 9 slopes towards the centre of the circular are so as to form a concave conical surface, and the contacting surface of the insulator 11 is shaped correspondingly so that its dependent portion 10 is Wedge shaped in vertical section. Thus if the rail and sleeper are angularly misaligned, that is to say they are not at 90 to each other, the insulator 11, because of the circular arc portion of the contact area, can still be fitted in position without large fitting tolerances (i.e. clearances) having to be provided. Further, this circular form on the shoulder and insulator means that any relative movement of the insulator 11 and sleeper 2 in the longitudinal direction of the rail 1 will cause the insulator 11 to become more tightly wedged between the shoulder 9 and the rail flange 6 and thus offer greater resistance to longitudinal movement of the rail 1. This interlocking of the shoulder 9 and dependent portion 10 of the insulator 11 also prevents longitudinal movement of the rail being transmitted to the clip 3. The wedge shaped vertical section of the insulator 11 facilitates insertion and removal of the insulator since there is no need to force the dependent portion 10 between parallel surfaces; moreover the wedging action of the insulators helps to position the rail flange centrally between the pair of shoulders 9 in course of installation.

At the ends of the circular pad of the contact area between the shoulder 9 and the dependent portion 10 of the insulator 11, the insulator 11 and the shoulder 9 diverge gradually from each other to prevent hard spots near the ends of the contact area between the shoulder 9 and insulator 11. This is accomplished by the shaping of the shoulder 9 such that the ends of its circular arc portion merge smoothly into curves 17 of reverse curvature that is from the concave circular arc portion to convex end portions. It could alternatively be achieved with the concave shoulder surface and the convex insulator surface shown in the drawings without reversing the curvature by providing the end portions of the shoulder surface with a larger radius of curvature and/ or the end portions of the insulator surface with a smaller radius of curvature than the circular arc portions defining the contact area.

The reaction piece 4 is fixed in the sleeper by two legs 4a depending from the cross-bar 5. The legs are nonconjoined and may be embedded in the sleeper by being cast therein or by being glued or grouted into a pre fonmed hole or holes in the sleeper. The legs may be straight or splayed as shown in FIGS. 3 and 4. The reaction piece can be simply and economically manufactured from material having a constant cross section such as bar metal of square, round or flat section. It can be made extremely stiff, with the further advantage that it will offer high resistance to accidental bending. The reaction piece 4 also contributes to the strength of the sleeper 2 by providing reinforcement in the vicinity of the rail seating and by resisting any tendency of the sleeper to split along a plane parallel to the longitudinal centre line of the sleeper.

The legs of the reaction piece 4 may be corrugated as shown at 19 in FIG. 4 or otherwise shaped to assist anchorage in the concrete.

With such arrangements of the reaction piece, it is possible without difficulty to avoid interference with reinforcement members such as bars or wires or with one or more cavities in the sleeper or other foundation, as there are no embedded cross parts or transversely extending connections. FIG. 4 illustrates how the legs of the reaction piece 4 lie on either side of the prestressed reinforcement wires 20 and a central hole 21, so that the longitudinal middle part of the foundation is not interfered with.

To improve the resilience of the insulator 11 and the bedding of the insulator 11 on the shoulder 9, the insulator may be relieved along the edge surface 13 engaging the side edge of the rail flange 6 for example by undercutting or angling edge surface 13 over that part of its length between the lines 14-14. As an alternative or additional way of improving the resilience of the insulator 11, the latter may be honeycombed as indicated by the chaindotted lines at 15.

To reinforce the shoulder 9, a steel plate as shown in chain-dotted line at 16 in FIG. 1 may be embedded in the material of the sleeper 2.

The concrete of the sleeper in the area under the rail and down to the boundary line 18 may be fibre-reinforced for example by short lengths of wire cord.

What we claim and desire to secure by Letters Patent is:

1. A rail fastening comprising, in combination with a rail foundation, a spring clip bearing on the rail flange, a shoulder on the rail foundation constituting an abutment for the flange, and a spacer disposed between the flange and the shoulder so that the flange abuts against the shoulder through the intermediary of the spacer, the shoulder and the spacer being of such shape that at least part of the contact area between them, as seen in horizontal section, describes an arc of a circle.

2. A rail fastening as claimed in claim 1, wherein the clip also bears upon the rail flange through the intermediary of the spacer.

3. A rail fastening comprising, in combination with a rail foundation, a clip bearing on the rail flange, a shoulder on the rail foundation constituting an abutment for the flange, and a spacer disposed between the flange and the shoulder so that the flange abuts against the shoulder through the intermediary of the spacer, the shoulder and the spacer being of such shape that at least part of the contact area between them, as seen in horizontal section, describes an arc of a circle and the circular arc portion of the contact area slopes towards the centre of the circular arc so as to form a conical surface, and the spacer is wedge shaped as seen in vertical section.

4. A rail fastening as claimed in claim 3, wherein at the ends of said circular arc portion, the shoulder and the spacer diverge gradually from each other by the shaping of at least one of said shoulder and spacer so that the circular arc portion of at least one of said shoulder and spacer merge smoothly into a different curvature.

5. A rail fastening as claimed in claim 4, wherein the circular arc portion of the shoulder is concave and merges into convex end portions.

6. A rail fastening as claimed in claim 4, wherein the circular arc portion of the shoulder is concave and of a first radius and merges into concave end portions having a larger radius.

7. A rail fastening as claimed in claim 4, wherein the circular arc portion of the shoulder is concave and the circular arc portion of the spacer is consequently convex and of a first radius as seen in horizontal section and wherein the circular arc portion of the spacer merges into convex end portions having a smaller radius as seen in that horizontal section.

8. A rail fastening as claimed in claim 3, wherein the spacer along that edge which engages the outer side edge of the rail flange is relieved over that part of its extension lengthwise of the rail where another of its edges provides said contact area with the shoulder.

9. A rail fastening as claimed in claim 3, wherein the spacer is formed with a structure between its surfaces which engage the rail flange and the shoulder, said structure being one of the following, namely, a honeycomb structure and an open cell structure.

10. A rail fastening as claimed in claim 3, wherein the clip is in the form of a spring plate, and comprising in addition, a reaction piece fixed in the foundation, the

reaction piece consisting of a cross bar and two nonconjoined depending legs together constituting an upright hoop located substantially in one plane, with its cross bar spaced above the surface of the foundation and away from the rail flange, and a back support mounted on the said foundation on the side of the said cross bar remote from the rail, the clip bearing at one end on the flange and at the other end on the back support and fitting intermediately of its ends, within the said hoop, where it reacts substantially in the said plane against the said cross bar.

11. A rail fastening as claimed in claim 10, wherein the legs of the reaction piece extend on either side of at least one of the following, namely, reinforcement members and a cavity in the foundation.

12. A rail fastening as claimed in claim 3, wherein the clip is in the form of a spring plate forked at one end for hearing on the rail flange and the spacer has a wall able to interengage with the forked end for preventing relative transverse movement between them.

13. A rail fastening as claimed in claim 3, wherein the rail foundation is of concrete and said shoulder is formed with fibre reinforcement.

14. A rail fastening as claimed in claim 3, the rail 6 foundation is of concrete modified by at least one of the following, namely, synthetic plastics material, rubber and bitumen.

15. A rail fastening as claimed in claim 3, wherein the rail foundation is of concrete and the shoulder is reinforced by a plate embedded in the concrete.

16. A rail fastening as claimed in claim 3, wherein the clip also bears upon the rail flange through the intermediary of the spacer.

References Cited UNITED STATES PATENTS 1,960,331 5/1934 Golbie l 238264 2,140,891 12/1938 Boyce 238349 2,570,871 10/1951 Schulze 238349 3,289,940 12/1966 Groif 238-2 9 ARTHUR L. LA POINT, Primary Examiner R. A. BERTSCH, Assistant Examiner US. Cl. X.R. 238264, 349