EP1499777B1

EP1499777B1 - Railway rail fastening clip

Info

Publication number: EP1499777B1
Application number: EP03747358A
Authority: EP
Inventors: Barry Marshall; Martin Somerset
Original assignee: Pandrol Ltd
Current assignee: Pandrol Ltd
Priority date: 2002-04-30
Filing date: 2003-04-04
Publication date: 2007-03-07
Anticipated expiration: 2023-04-04
Also published as: CN1650070A; CN1304696C; AR039503A1; DE60312313T2; GB2388141B; EP1499777A1; BR0309538A; MY131242A; UY27782A1; ECSP045398A; PE20031043A1; BR0309538B1; GB0209867D0; AU2003226532A1; GB2388141A; DE60312313D1; WO2003093580A1

Description

The present invention relates to a railway rail fastening clip.
In GB2199875A the present applicants disclosed a resilient railway rail fastening clip 90, as shown in Figures 1 and 2 of the accompanying drawings. The clip 90 is made of a rod of metal bent so as to have, proceeding along the rod from one end thereof to the other end, firstly a substantially straight first portion 10, then a bent second portion 20, then a substantially straight third portion 30 the axis of which makes an angle substantially more than 45° with the axis of the first portion 10, the two axes lying in the same plane as one another, then a fourth portion 40 which is a reverse bend, then a fifth portion 50, then a sixth portion 60 which is another reverse bend and finally a seventh portion 70 which forms the toe of the clip 90. When viewed from above, the fifth and seventh portions 50, 70 appear to be on opposite sides of the third portion 30.
In use on a timber sleeper 100 the clip 90 is placed so that the seventh portion 70 rests on a foot 120 of a rail 110, the first portion 10 projects into a blind round hole 140 in the sleeper 100, and a screwspike 130 is inserted between the third and fifth portions 30, 50 into the sleeper 100. In this way the clip 90 is retained in a position in which the toe 70 of the clip 90 bears on the rail foot 120 to hold down the rail 110 and lateral parts of the second and third portions 20, 30 of the clip 90 contact the edge of the rail foot 120 so as ensure gauge retention, i.e. so as to prevent sideways movement of the rail 110.
The applicants have now identified improvements which may be made to such a clip 90.
The hole 140 in the sleeper 100 into which the first portion 10 is inserted must be drilled slightly larger than the diameter of the first portion 10 (for example with a diameter of 15mm to accommodate a first portion 10 of 14mm diameter) so as to avoid the so-called "pneumatic effect" which can cause difficulty in entering the first portion 10 into the blind hole 140 and when extracting the first portion 10 of the clip 90 from the hole 140 during a track de-stressing operation. However, the first portion 10 should ideally be more close fitting in the hole 140 so as to control lateral movement of the.rail foot 120.
According to the present invention there is provided a resilient railway rail fastening clip, the clip being a rod of metal which has been bent so as to have, proceeding along the rod from one end of it to the other end, firstly a substantially straight first portion, then a bent second portion, then a substantially straight third portion the axis of which makes an angle substantially more than 45° with the axis of the first portion, the two axes lying in the same plane as one another, then a fourth portion which is a reverse bend, then a fifth portion, then a sixth portion which is another reverse bend and finally a seventh portion, the construction being such that it is possible to place the clip in a particular position such that the third portion is horizontal and the first portion extends downwardly and such that when the clip is viewed from above the fifth and seventh portions appear to be on opposite sides of the third portion, characterised in that the first portion is formed so as to comprise a region having a generally cylindrical surface extending along its entire length and a longitudinally-extending part having a surface which is less convex than the generally cylindrical surface region of the first portion.
Manufacturing the first portion of the clip in this manner removes the pneumatic resistance and allows the first portion of the clip to be inserted into, and extracted from, a blind hole in the sleeper more easily.
Preferably, the surface of the longitudinally-extending part is substantially flat.
Alternatively, the surface of the longitudinally-extending part is concave.
Typically, the rod forming the clip has a generally circular cross-section. In bearing against the rail edge to prevent lateral movement of the rail, the second and third portions of the prior art clip therefore make only line contact with the flat edge of the rail, as a consequence of which the contact pressures are high and premature wear takes place, generating a flat on the clip in these regions and consequently causing some slight gauge widening.
Preferably, therefore, in a clip embodying the present invention, at least part of the second portion and at least part of the third portion are manufactured so as to have substantially flat surfaces on respective lateral regions thereof which contact the rail when the clip is in use.
Thus, ,contact pressures between the flat surfaces of the second and third portions of the clip and the rail edge are much lower, significantly reducing wear on these regions of the clip.
Desirably, the substantially flat surface of the second portion is contiguous with the substantially flat surface of the third portion.
When the longitudinally-extending part of the first portion has a substantially flat surface, that surface is preferably contiguous with the substantially flat surface of the second portion.
Reference will now be made, by way of example, to the accompanying drawings, in which:-

Figures 1 and 2 (described above) show a prior art railway rail fastening assembly;
Figures 3 to 7 show respective perspective, plan, side elevational, front elevational and rear elevational views of a resilient railway rail fastening clip embodying the present invention;
Figure 8 shows a perspective, partially cut-away view of part of a railway rail fastening assembly incorporating a clip embodying the present invention;
Figures 9(A) to 9(D) are views for use in explaining a method of making a clip embodying the present invention; and
Figure 10 shows an alternative clip embodying the present invention.

As shown in Figures 3 to 9, a resilient railway rail fastening clip 9 embodying the present invention is formed from a rod of metal so as to comprise, proceeding from one end A of the rod to the other end B of the rod, a substantially straight first portion 1, a bent second portion 2, a substantially straight third portion 3, a bent fourth portion 4, a fifth portion 5, a bent sixth portion 6 and a seventh portion 7 forming the toe of the clip 9. The longitudinal axes of the first portion 1 and the third portion 3 lie in the same plane, the axis of the third portion 3 making an angle with the axis of the first portion 1. In the embodiment shown the angle α is 90°, but α could be any angle substantially more than 45°.
As in the prior art, the clip 9 is held down such that the toe of the clip bears on the rail foot 12 by a screwspike 13 screwed into the timber sleeper 15, the head of which screwspike 13 bears on the third and fifth portions 3, 5 of the clip.
The clip 9 is manufactured so as to have on the first portion 1 a region having a generally cylindrical surface 1B extending along its entire length and a longitudinally-extending part 1A having a surface which is less convex than the generally cylindrical surface region 1B. In this embodiment the longitudinally-extending part comprises a flat face 1A. The clip 9 is also manufactured in this embodiment so as to have a flat face 2A on the second portion 2 and a flat face 3A on the third portion 3, the flat faces 2A and 3A being on respective lateral regions of the second and third portions 2, 3 which contact the edge of the rail foot 12. For ease of manufacture the flat face 1A is contiguous with the flat face 2A, which is in turn contiguous with the flat face 3A, but this is not essential.
The flat face 1A on the first portion 1 serves to avoid the pneumatic resistance which would otherwise occur when the first portion 1 is inserted into a blind hole 14 in the sleeper 15 of the same, rather than slightly larger, diameter, thereby permitting a closer fit of the first portion 1 in the hole 14 and thus inhibiting lateral movement of the rail foot 12. As shown in Figure 10 the flat face 1A could be replaced by a concave channel 1C formed in the first portion 1 to achieve the same purpose, but for ease of manufacture it is preferable to have a flat face 1A, desirably on the same side of the clip as the flat faces 2A, 3A.
The pre-formed flat faces 2A and 3A on the second and third portions 2,3 of the clip 9 serve to prevent the gauge widening which would otherwise occur in these regions if they were of round cross-section and a flat face was worn on these regions. Such pre-formed flat faces could also advantageously be applied to a rail clip not having a flat face or concave channel on the downward leg.
A clip 9 having,the flat faces 1A, 2A and 3A can be made using the method illustrated in Figures 9(A) to 9(D). In Fig. 9(A) a pre-bent form is supported horizontally and the flat faces 1A, 2A and 3A are formed by pressing in the direction of arrow A. The partially-formed clip is then supported vertically (Fig. 9(B)) and a force applied in the direction of arrow B (Fig. 9(C)) to the part which is to form the seventh portion 7 in order to bend that part to its final shape, thereby forming a clip embodying the present invention (Fig. 9(D)).
The dimensions of a typical clip embodying the present invention, as identified in Figures 4 to 7 of the accompanying drawings, are as follows: 1=143mm, w=76mm, a=75mm, b=97mm, c=46mm, d=14mm, e=30mm, f=45mm, g=13mm, r1=8mm, r2=12.5mm and α=90°.

Claims

A resilient railway rail fastening clip (9), the clip (9) being a rod of metal which has been bent so as to have, proceeding along the rod from one end of it to the other end, firstly a substantially straight first portion (1), then a bent second portion (2), then a substantially straight third portion (3) the axis of which makes an angle substantially more than 45° with the axis of the first portion (1), the two axes lying in the same plane as one another, then a fourth portion (4) which is a reverse bend, then a fifth portion (5), then a sixth portion (6) which is another reverse bend and finally a seventh portion (7), the construction being such that it is possible to place the clip (9) in a particular position such that the third portion (3) is horizontal and the first portion (1) extends downwardly and such that when the clip (9) is viewed from above the fifth and seventh portions (5, 7) appear to be on opposite sides of the third portion (3), characterised in that the first portion (1) is formed so as to comprise a region (1B) having a generally cylindrical surface extending along its entire length and a longitudinally-extending part (1A; 1C) having a surface which is less convex than the generally cylindrical surface region (1B) of the first portion (1).
A clip as claimed in claim 1, wherein the surface of the longitudinally-extending part (1A) is substantially flat.
A clip as claimed in claim 1, wherein the surface of the longitudinally-extending part (1C) is concave.
A clip as claimed in any preceding claim, wherein the rod is of generally circular cross-section except at at least part (2A) of the second portion (2) and at at least part (3A) of the third portion (3) which are manufactured so as to have substantially flat surfaces (2A, 3A) on respective lateral regions thereof which contact the rail when the clip (9) is in use.
A clip as claimed in claim 4, wherein the substantially flat surface (2A) of the second portion (2) is contiguous with the substantially flat surface (3A) of the third portion (3).
A clip as claimed in claim 4 or 5, when read as appended to claim 2, wherein the substantially flat surface (1A) of the first portion (1) is contiguous with the substantially flat surface (2A) of the second portion (2).
A clip as claimed in any preceding claim, wherein the first portion (1) is free from helical parts which would facilitate screwing the clip (9) into a sleeper.