WO2014177835A1

WO2014177835A1 - A railway rail fastening clip

Info

Publication number: WO2014177835A1
Application number: PCT/GB2014/050988
Authority: WO
Inventors: Stephen John Cox; David Christopher HERRON
Original assignee: Pandrol Limited
Priority date: 2013-04-29
Filing date: 2014-03-27
Publication date: 2014-11-06
Also published as: GB2513565B; GB201307658D0; HK1198187A1; JP6143400B2; GB2513565A; JP2016514776A; TW201508131A; TWI621753B

Abstract

A railway rail fastening clip (10) comprising a rod (20) of resilient metal which, progressing from one end (A) of the rod to the other end (B), comprises: a first portion (11), which starts at one end (A) of the rod; a second portion (12); a third portion (13); a fourth portion (14); and a fifth portion (15) which ends at said other end (8) of the rod, wherein the second and fourth portions (12, 14) comprise reverse bends which are configured such that when the clip is viewed from above in an installed configuration, the third and fifth, portions appear to be on opposite sides of an axis of the first portion, wherein the fourth portion (14) comprises first and second subportions (14a, 14b), midlines (24a, 24h) of the first and second subportions having first and second radii of curvature (14a'. 14b' } respectively in a plane (P) substantially defined by the fourth portion, the first, radius of curvature (I4a') being greater than the second radius of curvature (14b').

Description

The present disclosure relates to a railway rail fastening clip,- I particular, bnt not exclusively, a railway rail fastening clip comprising a portion wit a changing radius of curvature.

B ckground Various forms of resilient rail clips are known, for example s shown ana described in GBlSi0224¾» Figaros 1, 2 and 3 of the accompanying drawings shows the prior art rail fastening asse bly disclosed in GBI510224A, In GBlS10224ft the applicant proposed a railway rail fastening clip of the type having a first portion 1, a bent second portion , a third portion 3._f a bent fourth portion 4_; and a fift portion 5. When the cli is in use the fifth portion 5 bears on the foot of a rail and extends in a direction substantially parallel to the longitudinal axis of that rail. The first portion 1 engages a passageway in a cli anchoring device and the third portion 3 bears on another part of the anchoring device_* In use, the railway rail fastening clip is in a stressed state so as to bear on the foot of the rail and hold the rail in place. In particular, the fastening clip is subject to vertical loads, which act on the first _f third and fifth portions and resuit in stresses in the fastening clip- In. addition, the fastening clip may be subject to lateral loads i a direction perpendicular to the

longitudinal axis of the rail, for example when a train passes over a portion of the rail that the fastening cli bears dow on, Such lateral loads may result in further stresses in the fastening c ip

It is desirable that the fastening clip withstands th stresses induced by the -vertical and lateral, loads in a reliable manner.

In this regard, the present disclosure: seeks to provide a railway rail fastening clip that may withstand the stresses induced by the vertical and lateral loads in a more reliable manner.

Suatements of 1 mention According to a aspect of the present invention there is provided a railway rail fastening clip comprising a rod of resilient metal which, progressing f om one and of the rod to the other end, comprises:

a first portion, which starts at one end of the rod? a second portion;

a third portion;

a fourth portion; and

a fifth portion which ends at said other end of the rod,

wherein the second and fourth portions comprise reverse bends which are configured such that when the cli is viewed from above in an: installed configuration, the third _:an.d. fifth portions appear to be on opposite sides of an axis of the first portion,

wherein the fourth portion comprises first and second subpcrtionS; midlines of the first and second snbportions having first and second radii of curvature respectively in a plane substantially defined by the fourth portion,, the first radius of curvature being greater han the second radius: of curvature.

The first subportion of the fourth, portion may be

positioned between the third portion and the second

subportion of the fourth portion.

The second subportion of the fourth portion may be at o near th geometric apex of the fourth portion. The second subportion of the fourth portion may be spaced apart from a midpoint of the fourth, portion. The midpoin may be half wa between the third and fifth portions. The second subportio of the fourth portion may be closer to th fifth portion than the third portion,

The fourth portion, may further comprise a third subportion. The third subportio may have a third radius o curvature. The third subportion of the fourth portion may be

positioned, between the fifth portion and the second

subportion of the fourth portion. The third radius of curvature may foe greater than the second radius of

curvature .

The first subportion: of the fourth portion may be adjacent to the third portion. The second subportion of the fourth portion may be ad acent to the fifth portion.

Alternatively, the third subportion of the fourth portion ma be adjacent to the fifth portion, e.g. with the third subportion between th second subportion and the fifth portion.

The first radius of eurvature may be greater than half of the distance between midlines of the third and fifth portions,. The first radius of curvature may be greater than or equal to 55% of the distance betwee midlines of the third and fifth portions. The first radius of

curvature may e greater than o equal to 60% of the distance between jjiidlines of the third and fifth portions.

The second radius of curvature may be lees than half of the distance between T¾|dlines of the third and fifth portions. The second radius of curvature may be less tha or equal to 451 of the distance between midllnea of the third and fifth portions. The second radius of curvatur may be les:s tha or sqnai to Q.% of the distance between midlines of the third and fifth portions, The distance between midlines of the third and fifth portions may be measured at ends of the third and the fifth portions adjacent to the fourth portion.

The fourth portion m y be shaped, so as to substantially lie in a plane. The fourth portion, plane may be angled with respect to a horizontal plane when the rail fastening clip is in n installed configuration_*

The rod may have a. length less^: than 20 times its thickness. l.n particular, the rod may have a length less than 18 times its thickness.

The: above-mentioned radii of curvature may apply to a midline of the rod,

The sufoportions of the fourth portion may have different centres of rotation . A transition between the first anil second sabpo tiona of the fourth portion may foe at a point wa f om either end of the fourth portion > A railway rail fastening ssembly may comprise the above-- mentioned railway rail fastening clip.

Brief Descri tion of the Drawlnos Reference will now be made to. the accompanying drawings in which:

Figure 1 shows a side view of a previously-proposed railway rail fastening clip taken, in the direction of arrow I in Figure 2;

Figure 2 shows an end view of the same clip, taken in the direction of arrow 11 in Figure 1; Figure 3 shows a plan view of the s m clip;

Figure 4 shows a side view of a railway rail fastening clip according to an. embodiment of the present invention taken in the direction of arrow V in Figure 5;

Figure 5 shows an end view of th clip according to the embodiment of the present invention, taken in the direction of arrow IV in Figure 4; Figure 6 shows a plan view of the clip according to the embodiment of the present invention; Figure 7 sho»?s a iew of the clip according to the

embodiment of the present invention normal to a plane defined by th fo.urth portion (the first portion has been omitted for clarity) ; and

Figure 8 shows stress contour lines for the previously- proposed clip (Figure 8 (a)} and the cli according to. the embodiment of the present invention (Figure 8(b)) . beta.i1.ed_.JPescriptjon

With reference to Figures 4, 5, 6 and 7, a railway rail fastening cli ID according to an eisbodiTaent of the present invention comprises a rod 20 which, progressing from a first end Ά of the rod to a second end B, comprises; a first portion 11, which starts at the first end of the rod A a second portion 12; a third portion 13; a fourth portion 14; and a fifth portion 15, which ends at the second end S of the rod, hs: shewn in Figure 6, the points where these portions meet is m rked approximately by the line 11-12, 12-13 , 13-14, 14-15,

The first and fifth portions 11, 15 are substantially straight. By contrast ,· the second and fourth portions 12, 1 comprise reverse bends, which are configured such that when the clip is vi wed frors above in an installed

configura ion (e.g. as depicted in Figure 6), the third and fifth portions 13, 15 appear to be on opposite sides of a midline 21 o the first portion XI, In other words, the average radius of curvature for the fourth portion 14 is greater than, that for the second portion 1.2, ?

As depicted in Figure 4, a midline 24 of the fourth portion 14 substantially lies in. a plane F which is angled wits respect to a horizontal plane H when in the installed co.nfiguration - (Figure ? is a view of the fourth portion 14 normal to the plane P of the fourth portion,)

Accordingly,, the third portion 13 may om rise: a subportion 13a adjacent to the second portion 12, and a subportion 13b adjacent to the fourth portio 1 , The subpoxtions 13a, 13b may be d, e,g. in different planes, so as. to provide a transition from the second portion 12 to the fourth portion 14. For example, the subportion 13 may bend from the plane of Che second portion 12 to the plane P is which the fourth portion substantially lies. In. use, the fifth portion 15 is configured to bear down on a rail (not shown), either directly or via an insulator. The fifth portion 15 may comprise a flattened face 15a for contacting the rail. The third portion 13 may bear down on an anchoring device (not shown) and the first portion 11 may reside in. a receiving portion,- e.g. bore of the anchoring device, Alternatively, the clip 10 may be orientated the other way round, with the third and fifth portions ll, 15 bearing down on the rail and the anchoring device respectively,

The rod 20 may deform when installed so as to provide a force bearing down on the rail, Accordingly, the rod 20 may be made of metal, e.g. a resilient metal. The clip 10 may be formed by bending the rod 20 about one or more for .ers. In terms of its dimensions, the rod 20 may have a length approximatel 17.9 times its thickness. As best depicted in Figure 7, the fourth portion 1

cor¾>rises first and second, subportions 14 a, 14fo, he first subportion 14 of the fourfb portion 14 may be positioned between the third portion 13 and the second subportio 14b of the fourth portion 14» Accordingly, the first

subportion 14a of the fourth portion 14 may be adjacent to the third portion 13. The second subportion 14b of the fourth portion 14 laay be at or near a geometric apex of the fourth portion, e.g. the point furthest from the third and/o fifth portions 13, 15.

It will be appreciated that a transition i4a~14h between the first and second subportions 14 14b of the fourth portion is a a point away from either end of the fourth portion 14. The transition I4 ~!4fo may be at or near the geometric- apex of the fourth portion 14,.

Midlines 24a, 24b of the first and second subportions :14a, 14b have first and second radii of curvature 14a/ , 14fo* respectively in a plane substantially defined by the fourth portion, e.g. as depicted in Figure 7. (NB, the midlines 21, 22, 23, 24, 25 of respective portions 11, 12, 13, 14, 12 of the rod 20 co res onds to a line substantiall y through the centre of the rod_*} The first radius of curvature 1 a ' is greater than the second radius of curvature 1 b' .

As depicted, the fourth portion 14 ma further comprise a third subportion 14c, however in an alternative arrangement (not shown) _f the third subportion ma be emitted. The third subportion 14c of the fourth portion may be

positioned between the fifth portion 15 and the second subportion 14b of the fourth portion 1.4» The third subportion. 14c of the fourth portion 14 may b adjacent to the fifth portion 15, Alternatively, in the case of the third subportion 14c being omitted, the second subportion i<; of the fourth portion 14 may be adjacent to the fifth portion IS.

It will he appreciated that, a transition 14b—14c between the second and third subportions 14b, 14c of the fourth portion is at a point away from either end of the fourth portion 14.

The midline 24c or the third subportion may have a third radius of curvature 14c' . The third radius of curvature T4c' may be greater than the second radius of curvature 14h' t The first and third radii of curvature 14a ^? ^ 14c'^" may be substantially equal.

The first radius of curvature 14a' may be greater than half of the distance D between the midlines .23, 25 of th third and fifth portions 13, 15 where the third and fifth portions meet the fourth portion 14. The first radius of curvature 14a' may be greater than o equal, to 55% of the distance 0 between the midlines 23, 25 of the third and fi th, portions.

The second radius of curvature X4b' ma e less than half of the distance D between midlines 23, 25 of the third and fifth portions. The second radius of curvature 14b^f may be les than or equal to 45% of the distance D between midlines 23, 25 of the third and fifth portions.

With reference t_:o Figure 7, a first angle 14a'^'' subtended by the first subportion 1.4a: may be greater than a second angle i.4b' * subtended by the second subpartio - 1.4b.

S.m-b lar i y, a third, angle 14c' ^f subtended by the third subportion 14c may fee greater than the second angle 1 ··b¹ ' subtended, by the second subportion 14h, The first angle 14a" subtended by the first subportion 1.4a ay be greater than the third angle 1.4c' ' subtended b the third

snbport1o 14 e .

Again with reference to Figur 1, the length of the arc along the midline 24a forming the first subportion 14a may be greater than the length o the arc forming the second subportion 14b, Similarly, the length of the arc along the midline 24o forming the third Subportion 14c may be greater than the length of the arc forming the second subportion 14b, The length of the arc along the midline 24a forming the first subportion 14a may be greater than the: length of the arc forming the third, subportion 14c,

In a particular example, the first, second and third sabportions 14a, 14fo, lie _:of the fourth portion 14 hav inner radii of curvature of approximat ly 40 m , 20 mm and 40 mm respectively, that is the radius of curvature from the centre of rotation, to the inner edg of th rod 20. (In other words, these are the radii of the formers around which the rod is bent to form the subportions 14a , 14b,

14c.) In the par. lea ar example,, the rod 20 has a diameter of 19 m ., As such, the first, second and. third radii of curvature 14a' , 14b', I4 ^r , which are measured from the respective centre of rotation to the respective, midline a, 24b, 24c of the rod 20, are approximately 49,5 m,

29,5 mm, and 49.5 mm respectively. The distance between the midline 23 of the third portion 13 to the midline 25 of the fifth portion .15, where they meet the fourth portion 1 , is approximately 80 mm.

In the particula .exam le, shown, the first sufoportion 14a may be subtended by first angle i4a'^? of approximately 70110 degrees, the second sub-portion 14b may be subtended by second, angle 1 *3' of approximately SS11Q degrees and the third s foportion 14c may be subtended by a third angle 1^■" :.' ' of approximately 55110 degrees . However, it vs.il 1 be appreciated that othe angles may be selected for the first, second and third sufoportions.

Figure 8(a) shows stress contours for third and fourth portions 3, 4 of a previously-proposed: railway clip

subjected to a given deflection. The deflection, includes a vertical component; which includes the static deflection applied to the clip upon lostalia: lee, and a dynamic lateral, component_s which occurs when a train passes over a portion of the rail that the fastening cli bears down on, As dep cted, there are low, medium and hig stress regions IsS, MS,, MS in the fourth, portion 4. In particular _f the high stress region HS is in a region of the fourth portion towards the third portion 3, By contrast , Figure 8(b) shows equivalent stress contours for the third and. fourth, portions 13., 14 of a railway clip according to the embodiment of the present inventio

subjected to the same deflection as for Figure 8(a). As depicted;, there are low and medium stress regions hh , MS in; the fourth portion. 14 _r but no high stress region with the embodiment of the present invention. The clip of the present invention better distributes the dynamic stresses around, the third and fourth, portions and the maximum dynamic stress. experienced by the cli is .lower.

The present invention therefore_^advantageously reduces the stresses in the fourth portion 14. This in turn enables a itiore reliable railwa cli and/or a reduction in the diartieter of the el ip, thereby s ving material.

Claims

Cl ims

1, A railway rail fastening clip comprising a rod of resilient metal which, progressing from one end^' of the rod to the other end, c mprises :

a first portion, which starts at one end of the rod? a second portion;

a third portion;

a fourth portion; and

a fifth portion which ends at said other end of the rod,

wherein the second and fourth po tions comprise reverse bends which are configured such that when the clip is viewed from above in an. installed configuration, the third and fifth portions appear to foe on opposite sides of an axis of the first portion,.

wherein the fourth portion comprises first and second ubportione , midlines of the first and second s bcortices having first and second, radix of curvature respectively in a plane substantially defined by th fourth portion, the first radius of curvature being greater than the second radius of curvature.

2, The railway rail fastening clip of claim 1, wherein the first subportion of the fourth portion is positioned between the third portion, and the second subportion of the fourth portion.

3, The railway rail fastening cli of claim 1 or 2, wherein the second subportion of the fourth portion is at or near the geometric apex of the fourth portion.

. The railway rail f stening clip of any of the preceding claims _ί wherein the second subportion of the fourth portion is spaced- apart from a midpoint of the fourth portion. 5. The railway rail fastening clip of any of the preceding claims, wherein the second snhportion of the fourth portion is closer to the fifth portion than the third portion,

6 The railway rail fastening clip of any of the preceding claims, wherein the fourth portion further comprises a third siibportioH, a midline of the third subportion having a third radius of curvature.

7, The railway rail fastening clip of claim 6, wherein th third subportion of the fourth portion is positioned between the fifth portion and the second subportion of the fourth portion.

8, The railway rail fastening clip of claim 6 or ?, wherein the third radius of curvature is greater than the second radius of eurvature.

9» The railway rail fastening clip of any of the preceding cl ims> wherein the first radius of curvature is greater than half of the distance between midlines of the third and fifth portions,

10. The railway rail fastening clip of claim 9, wherein the first radius of curvature is greater than or egual to 5S¾ of the distance between midlines of the: third and fifth portions, 11, The railway rail fastening cli of any of the preceding clairas, wherein the second radios of curvatur is less than half of the distars.ce between midlines of the third and fifth portions,

12, The railway rail fastening clip ©£· claim 11, wherein the second radius of curvature is less than or equal to 45% of the distance between nrldlines of the third and fifth por ion .

13, The railway rail fastening clip of any of the preceding claims, wherein the fourth portion is shaped so as to substantially lie in a plane, 14» The railway rail fastening clip of claim 13, wherein the fourth portion plane is angled with respect to a hori rental plane when the rail fastening clip is in a insta.1 led eonfiguraf on . 15 A railway rail fastening ass mbly comprising the railway rail fastening clip of any of the preceding -laims ,

16. A railway rail fastening clip or railway rail fastening assembly substan ially as described herein with reference to and as shown in Figures to 8.