GB2142068A

GB2142068A - System for securing a railway rail to a railway sleeper

Info

Publication number: GB2142068A
Application number: GB08316855A
Authority: GB
Inventors: Barry Marshall; Thomas Troth
Original assignee: AE PLC
Current assignee: AE PLC
Priority date: 1983-06-21
Filing date: 1983-06-21
Publication date: 1985-01-09
Also published as: GB8316855D0; GB2142068B

Abstract

In a system for securing a railway rail 24 to a railway sleeper 25 an I-shaped locking key 12 is passed through an aperture 17 in a spring plate clip 11 into a sleeper slot 28 and is turned through 90 DEG to lock. The lower arms 23 of the key 12 are thus engaged under the slot 28 in the sleeper while the upper arms 22 of the key exert a downward pressure on the spring plate 11. The clip 11 is chevron-shaped in plan, whereby the pressure is transmitted to the flange 26 of the rail 24 and to the sleeper 25 through a pair of toes 13, 14 and a single heel 16. <IMAGE>

Description

SPECIFICATION System for securing a railway rail to a railway sleeper The present application relates to the securing of a railway rail to a railway sleeper. A number of methods have been employed to secure rails to sleepers. One of the simpler methods has been to place a plate so that it straddles the rail flange and the sleeper and then to nail this in position. This arrangement suffers the disadvantage that it is only really practicable with wooden sleepers and second ly these can become damaged and sometimes split as the nails are driven home. Thus, the sleepers may not be reusable.

In another known method a rail clip is used, made from a bent rod of metal. The rod is bent through 180" twice to leave two ends on either side of the bends and an intermediate section between the bends. The two ends and the intermediate section lie generally parallel to one aotherwith one end between the other end and the intermediate section.

Such a clip is used in conjunction with a loop or the like which is fixed to the sleeper, the "middle" end of the clip being located within the loop while the other end engages the rail flange and the intermediate portion the sleeper.

This construction tends to suffer the disadvantage that it is either comparatively difficult to locate the clips or it requires fairly complicated and heavy machinery. It tends to be even more difficult to remove these clips.

In another construction, an inverted U-shaped yoke is attached to the sleeper adjacent the rail and a spring plate is forced beneath the yoke so that it presses downwardly on the sleeper and the rail flange. In such a construction the yoke is either cast in position in the sleeper or bolted to it. Once again, it tends to be rather difficult to position the spring plate correctly since it is necessary to move the spring plate while it is in a stressed and deformed state.

It is an object of the present invention to provide a method of attaching a rail to a sleeper which can be carried out quite simply using inexpensive materials and without the need to resort to complicated machinery.

According to the present invention, there is provided apparatus for securing a railway rail to a railway sleeper comprising a spring plate and a locking member, the spring plate having a first engagement zone arranged to engage the rail flange, a second engagement zone arranged to engage the sleeper and an aperture between the first and second zones, and the key member having a bottom portion which is releasably connectable to the sleeper, a top portion which engages the spring plate and an intermediate portion which extends through the spring plate aperture and is so dimensioned that when the bottom portion is connected to the sleeper, the top portion exerts the pressure on the spring plate which is transmitted to the sleeper and rail flange. The engagement zones need not engage the rail flange and sleeper directly but may do so through some intermediate means.

The spring plate is preferably generally chevron shaped so that at one end it terminates in a V while at the other end there is a corresponding V cut out to define two toes. The toes preferably define the first engagement zone while the Vat the other end is preferably bent over to define a heel. The spring plate is preferably generally concave with the heel and toes providing the lowest points and the aperturn the highest.

The spring plate may be indented on either side of the aperture to provide a location for the locking member.

The locking member is preferably in the form of an I-shaped key. The lower arms of the key are preferably large enough to pass directly through the aperture in the spring plate while the upper arms of the key are not. Thus, the key may be inserted through the aperture until the lower arms engage in a slot in the sleeper and the upper arms abut the top surface of the spring plate. In the case of such an embodiment, it is necessary for the sleeper slot to comprise a relatively narrow opening covering a wider hole beneath. In the case of concrete or timber sleepers, a suitable metal base plate having a narrow opening can be located over a larger hole formed in the sleeper. Such a base plate may not be necessary in the case of steel sleepers.

To lock the spring plate in position, holding the rail to the sleeper, the spring plate is first positioned so that the toes lie on the rail flange and the heel is located in a suitable recess in the sleeper. The key is placed in position so that its lower arms lie in the sleeper slot. The key is then turned about a vertical axis so that the lower arms are locked within the sleeper slot and the upper arms lie across the spring plate in a transverse direction. Preferably, the shank of the key between the upper and lower arms is so dimensioned that is is necessary to distort the spring plate somewhat from its naturally convex shape in order that the lower arms can be locked within the sleeper slot. In this way, the toes and heel will be stressed downwards against the rail flange and sleeper respectively.

As will be appreciated, the only tool necessary to install such a securing arrangement would be a simple tensioning lever to depress the central part of the spring plate so that the key can be turned manually. Furthermore, by varying the length of the key shank or the length of the spring plate heel, different toe load requirements can be achieved and different rail sections can be accommodated. A further advantage of the two-toe arrangement is that this construction can accommodate mis-alignments and mis-orientations between the sleeper and rail.

The arrangement also enables high toe loads to be applied in limited head-room fastening applications.

According to another aspect of the invention, there is provided a method for securing a railway rail to a railway sleeper which comprises placing the rail on a sleeper; placing a locking member through an aperture in a spring plate; positioning the spring plate so that a first zone engages the rail flange while a second zone engages the sleeper; locating the bottom portion of the locking member in a slot in the sleeper; and locking the locking member in the slot releasably, so that the two spring plate zones exert a downward pressure on the rail flange and the sleeper.

The invention may also encompass a railway assembly comprising a rail having a rail flange, a sleeper having an engagement slot, a spring plate engaging the rail flange and the sleeper, and a locking member having a top portion engaging the spring plate, an intermediate portion extending through an aperture in the spring plate and a bottom portion releasably connected with the slot in the sleeper whereby the spring plate is tensioned against the rail flange and the sleeper by the reaction between on the one hand the locking member and the sleeper and on the other hand the locking member and the spring plate.

The invention may be carried into practice in various ways and one embodiment will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a plan view of a blank cut out from unhardened steel for forming into the spring plate; Figure 2 is a side view of the blank of Figure 1 after having been formed into the spring plate; Figure 3 is an isometric sketch of the spring plate; Figure 4 is an isometric sketch of the locking key; Figure 5 is a side view of the spring plate and locking key in position relative to a rail and a sleeper; and Figure 6 is a plan view corresponding to Figure 5.

Referring firstly to Figures 1 to 4, the apparatus for securing a railway rail to a railway sleeper comprises a spring plate 11 and a tensioning key 12.

The spring plate 11 is cut from an unhardened spring steel strip 4.5mm thick and initially has a chevron-like shape as shown in Figure 1. Thus, the plate 11 comprises a pair of toes 13, 14 defined buy a generally V-shaped cut-out 15 and a heel 16 defined by a generally V-shaped protrusion. As will be seen, the V-shaped cut-out 15 and the V-shaped protrusion have complementary shapes to minimise wastage of material in forming the plates. A generally rectangular aperture 17 is formed in the spring plate 11, in the central portion 18 located between the V-shaped cut-out 15 and the V-shaped protrusion. The aperture 17 extends generally longitudinally of the spring plate 11.

Prior to use, the spring plate 11 is bent to the shape shown in Figure 2. thus, the spring plate 11 is arched about a generally transverse axis so that the aperture 17 is at the highest point. The toes 13, 14 are bent upwards and the heel 16 is bent downwards. In an alternative form, the central portion 18 is bent to the shape shown in broken lines in Figure 2 to define a transverse indentation 19 on either side ofthe aperture 17.

The key 12 is made from a Corten material and comprises a shank 21, a top cross-piece 22, and a bottom cross-piece 23. The bottom cross-piece 23 is small enough to pass through the aperture 17, however, the top cross-piece 22 is larger and unable to pass through the aperture 17.

Figures 5 and 6 show how the spring plate 11 and the key 12 are used to secure a rail 24 to a sleeper 25.

The rail 24 has a rail flange 26 which sits upon the sleeper 25. The sleeper 25 has a pair of detents 27 against which the rail flange is positioned, a slot 28 covering a cavity 29, and a small locating hole 31.

To secure the rail to the sleeper, the bottom cross-piece 23 of the key 12 is passed through the aperture 17 so that the top cross-piece 22 rests along the top of the spring clip 11. The spring clip 11 is then positioned with the toes 13, 14 on the rail flange 26 and a locating tab 32 on the heel 16 located in the hole 31 in the sleeper 25. The spring clip 11 takes up the position shown in chain lines in Figure 5. The key 12 is adjusted so that the top cross-piece 22 lies along the length of the spring plate 11 and the bottom cross-piece 23 lies in the slot 28 in the sleeper 25.

The spring plate 11 is then depressed to the position shown in Figure 5 so that the bottom cross-piece 23 lies within the cavity 29 in the sleeper 25. The key 12 is then turned through 90" so that the cross-piece 22 and 23 are transversely orientated with respect to the spring plate 11 is shown in Figures 5 and 6. In this position, the bottom crosspiece 23 is trapped within the cavity 29 thus tensioning the spring plate 11 so that the toes 13, 14 exert a pressure on the flange 26 and the heel 16 exerts the pressure on the sleeper 25.

As can be seen in Figures 5 and 6 the top cross-piece 22 is located behind the highest point of the upper surface of the spring plate 11, with the shank 21 abutting the most rearward surface of the aperture 17. In the alternative construction shown in Figure 2, the top cross-piece 22 of the key 12 would like in the indentation 19.

The preferred method of depressing the spring plate 11 is to use a tensioning lever which could conveniently locate in fulcrum holes (not shown) in the sleeper 25. The key 12 can then be turned through 90" manually.

In orderto remove the spring plate 11 and key 12, the above procedure is simply carried out in reverse.

Claims

1. Apparatus for securing a railway rail to a railway sleeper comprising a spring plate and a locking member, the spring plate having a first engagement zone arranged to engage the rail flange, a second engagement zone arranged to engage the sleeper and an aperture between the first and second zones, and the locking member having a bottom portion which is releasably connectable to the sleeper, a top portion which engages the spring plate and an intermediate portion which extends through the spring plate aperture and is ao dimensioned that when the bottom portion is in engagement with the sleeper, the top portion exerts a pressure on the spring plate which is transmitted to a rail flange and sleeper via the first and second engagement zones respectively.

2. Apparatus as claimed in Claim 1 in which the spring plate is generally chevron-shaped, terminating at one end via a V-shape while having at the other end a V-shaped cut-out defining two toes.

3. Apparatus as claimed in Claim 2 in which the toes define the first engagement zone and the V-shaped end is bent over to define a heel which comprises the second engagement zone.

4. Apparatus as claimed in any preceding claim is generally concave with the heel and toes providing the lowest points and the aperture the highest point.

5. Apparatus as claimed in any preceding claim in which the locking member is an I-shaped key whose lower arms are dimensioned to pass through the aperture in the spring plate and whose upper arms are not.

6. Apparatus for securing a railway rail to a railway sleeper constructed and arranged substantially as herein specifically described with reference to and as shown in the accompanying drawings.

7. A method for securing a railway rail to a railway sleeper which comprises placing the rail on a sleeper; placing a locking member through an aperture in a spring plate; positioning the spring plate so that a first zone engages the rail flange while a second zone engages the sleeper; locating the bottom portion of the locking member in a slot in the sleeper; and locking the locking member in the slot releasably, so that the two spring plate zones exert a downward pressure on the rail flange and the sleeper.

8. A method as claimed in Claim 7 in which the spring plate is distorted from a naturally convex shape when the locking member is in position.

9. A method as claimed in claim 7 or Claim 8 in which a tensioning lever is used to depress the control part of the spring plate to enable the locking member to be located in position.

10. A method for securing a railway rail to a railway sleeper substantially as herein specifically described with reference to and as shown in the accompanying drawings.

11. A railway assembly comprising a rail having a rail flange, a sleeper having an engagement slot, a spring plate engaging the rail flange and the sleeper, and a locking member having a top portion engaging the spring plate, an intermediate portion extending through an aperture in the spring plate and a bottom portion releasably connected within the slot in the sleeper whereby the spring plate is tensioned against the rail flange and the sleeper by the reaction between on the one hand the locking member and the sleeper and on the other hand the locking member and the spring plate.