GB2045320A

GB2045320A - Rail Securing Arrangement

Info

Publication number: GB2045320A
Application number: GB8007673A
Authority: GB
Original assignee: Hoesch Werke AG
Current assignee: Hoesch Werke AG
Priority date: 1979-03-26
Filing date: 1980-03-06
Publication date: 1980-10-29
Also published as: DE2911825C2; JPS55129501A; AU535645B2; PL130979B1; CA1145729A; IN152207B; PL222995A1; MX149974A; AT366123B; IT8048107A0; FR2452546B1; ATA7780A; DE2911825A1; GB2045320B; AU5616480A; BR8001787A; NL8001406A; ES488621A1; ZA801760B; FR2452546A1

Abstract

In a spring-stressed rail securing arrangement for concrete sleepers or paved track a spring clamp device bent from steel bar has a shaft (102) extending through an abutment plate (40) and an aperture in the concrete sleeper (30), or paved track. The leading end of the shaft (102) has a claw (103), which, when in the clamped condition, positively engages underneath a holding plate (302) facing the underside of the concrete sleeper or the underside of the paving. A spring loop (101) of the clamp has a holding a finger (105) for holding down the foot (201) of the rail, either directly or through the intermediary of the abutment plate (40), whilst a clamp limit stop (104) bears upon the abutment plate (40). <IMAGE>

Description

SPECIFICATION Rail Securing Arrangement The invention relates to a spring stressed rail securing arrangement for use with concrete sleepers or a permanent way without sleepers.

For securing rails to concrete sleepers, or to a permanent way without sleepers, securing means have already been introduced, in which spring elements are clamped by screw spikes of the coach bolt type in such manner that the spring elements hold down the rail when the screw spikes are screwed into the concrete sleepers, or concrete plates, by means of intervening plugs of synthetic plastics material or wood.

In the case of wooden sleepers rail spikes according to DE-PS 1106 788 have proved to be satisfactory. The spring rail spikes afford the advantage of achieving a consistently good clamping of the rail upon the sleeper at a low cost, for example as shown by a screwed down spring rail securing device according to DE-P-S 1 257 817. Various attempts have been made to introduce spring rail spikes in cases where concrete sleepers are used or where the permanent way is without sleepers. As an example DE-PS 1 241 857 may be cited. The practical problems encountered in installing spring rail spikes for concrete sleepers are based upon the fact that the frictional value between steel and concrete is small as contrasted with that between steel and wood.An attempt has been made according to DE-PS 1 241 857 to compensate for the smalier adhesion obtainable between concrete and steel by the introduction of spring rail spikes in which the shaft is given a spring bias. This arrangement acknowledges the fact that when driving the shaft of the spring spike into wood, the wood yields elastically. In the case of concrete there is no such elasticity.

According to the known state of the art, it is not possible to obtain the necessary clamping force with a spring spike fastened in a concrete sleeper. An attempt to make the clamping stress of the spike shaft in the bore of the concrete sleeper sufficiently large to afford the required holding force of the spring spike, results in the stress limit of the concrete being exceeded, so that the concrete sleeper splits parallel to the reinforcement. If the prestress on the shaft of the spring spike is reduced to such an extent as not to impair the strength of the concrete sleeper, then it is impossible to obtain an adequate holding down force.

It would accordingly be advantageous to provide a spring stressed rail securing arrangement which is suitable for use in concrete sleepers or in a permanent way without sleepers, and which offers mechanical properties and a simplicity of installation equivalent to those of a spring spike.

The invention accordingly provides a spring stressed rail securing arrangement for use with concrete sleepers or a permanent way without sleepers, the arrangement comprising a spring clamp, the spring clamp having a shaft extending through an abutment plate and an aperture in the concrete sleeper, or in the permanent way without sleepers, a claw at the leading end of the shaft which positively engages beneath a holding surface in the clamped condition, a spring loop with a holding finger holding down the foot of the rail, either directly or through the abutment plate, and a clamp limit stop bearing the abutment plate.

A rail securing arrangement embodying the invention advantageously incorporates one or more of the following features: a) the clamp limiting stop also is designed to have the form of a spring loop, and the two spring loops may then be differently constructed; b) the claw at the leading end of the shaft is positioned outside the free cross-section of the aperture when the device is in the clamping position; c) the holding plate for the claw is constructed in a spiral configuration; and d) the aperture penetrated by the shaft is of keyhole shape.

Positive connections between a sleeper and a rail securing device are already known from DE PS 3 194 and DE-PS 537 117. However, this prior art makes no contribution to the present inventive concept because these prior published proposals, in the first place, do not relate to spring securing devices for rails and, secondly, are not intended for use with concrete sleepers or with a permanent way without sleepers.

The advantages afforded by the present invention are that a simple and functionally reliable securing means is provided, which satisfies all the requirements for spring rail fixing means upon concrete sleepers, or a permanent way without sleepers. Furthermore, the rail securing arrangement is capable of extremely simple assembly and dismantling, whilst the position of the rail can already be determined before the clamping of the rail is completed.

The invention is further described below, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a sectional view through a first rail securing arrangement embodying the invention taken at right angles to the length of the rail; Fig. 2 is a plan view of the rail securing arrangement of Fig. 1; Fig. 3 is a plan view of a second rail securing arrangement embodying the invention; Fig. 4 is a sectional view corresponding to that of Fig. 1 showing the rail securing arrangement of Fig. 1 a mounting position; and Fig. 5 is a sectional view corresponding to that of Fig. 1, showing a modified form of the rail securing arrangement of Fig. 3.

In all of Figs. 1 to 5, rail securing arrangements embodying the invention are shown in combination with a rail 20 and a concrete sleeper 30. No modification need be made in the rail securing arrangements when installed in a permanent way having no sleepers.

The rail 20 rests upon the concrete sleeper 30 and an interposed bedplate 501. Lateral support for the rail is provided by means of an abutment plate 40, which bears at one side against the foot 201 of the rail, and at the other side has a portion 401 with a bevelled surface bearing against a similarly bevelled seat 303 of the sleeper 30.

Between the concrete sleeper 30 and the abutment plate 40 there is arranged a bedplate 502. The function of holding down the rail is performed by a spring clamp 10 bent from steel bar. A spring loop 101 of the clamp 10 terminates in a holding finger 105 which bears upon the foot 201 oftherail.

In a modified arrangement, not shown in Fig. 1, the abutment plate 40 is arranged to engage over the foot 201 of the rail, and the holding finger 105 of the spring loop 101 bears upon this abutment plate 40.

A shaft 102 of the spring clamp 10 extends through the abutment plate 40 and through an aperture 301 provided for that purpose in the sleeper 30. The shaft 102 of the spring clamp 10 is formed at the leading end with a claw 103, which engages a holding plate 302 bearing against an underside of the concrete sleeper 30.

In the illustrated arrangement, the holding plate 302 has the form of an insert 304 of special material in the concrete sleeper 30. A clamp limit stop 104 provided on the spring clamp 10 bears against the abutment plate 40 when the arrangement is in the clamped condition.

In the alternative form of device shown in Figs.

3 and 5, the shaft 102 of the clamp 10, instead of being provided with the clamp limit stop 104, is made, over the appropriate part, of a double steel bar, so that the shaft terminates in a second spring loop 106, which is then provided with a second holding finger 107 bearing upon the abutment plate 40.

In assembling the spring stressed rail securing arrangement according to the invention, the spring clamp 10 is inserted from above into the mounting position as shown in Fig. 4 so that the shaft 102 and the claw 103 pass through the aperture 301. For this purpose the aperture 301 is advantageously of keyhole shape. The mounting position shows the spring clamp 10 so iocated that the abutment plate 40 is fixed, but leaving free access for the rail 20 to be mounted in position from above. Consequently the concrete sleepers 30 can all be delivered to the erection site together with the preassembled rail fittings. For bringing the arrangement into the clamped condition there are two possible methods.

According to the first method, the holding plate 302 is of spiral shape. By rotating the spring clamp 10 out of the mounting position into the operating position, the claw 103 at the end of the shaft 102 performs a screwing motion downwardly over the spiral shaped holding plate 302. In this way the necessary clamping force is applied in the operating position.

According to the second method of the arrangement is brought into the clamped condition by the aid of clamping tools. This is done by first depressing the spring clamp 10 when in the mounting position and then rotating it into the operating position. After being rotated the spring clamp 10 cannot release itself because in the operating position the claw 103 positively engages underneath the holding plate 302.

By constructing the spring clamp in accordance with Figs. 3 and 5, with two different spring loops, correspondingly different clamping forces are exerted upon the shaft 102 of the spring clamp 10. A bending moment is thereby applied to the shaft, which has the effect that the claw 103 at the end of the shaft 102 is positively engaged underneath the holding plate 302 without any further steps being necessary. When dismantling the spring clamp 10 of this construction, it is necessary to apply a corresponding opposing moment to the spring loops 101, 106, in order to make it possible to withdraw the claw 103 through the free space provided by the aperture 301.

As shown in Fig. 5, it is possible to provide sideways adjustment of the rail 20 in the rail securing arrangement according to the invention.

For this purpose there are inserted, in known manner, lateral adjustment shims 60 of various thicknesses between the inclined seating surface 303 of the concrete sleeper 30 and the bevelled face of the ambutment plate 40. In order to provide the sideways adjustability the aperture in the abutment plate 40 must possess the necessary extra clearance.

Moreover, Fig. 5 shows a modification of the arrangement, wherein a nosepiece 402 is provided on the support plate to enable the spring clamp 10 to hold down the foot 201 of the rail.

Claims

1. A spring-stressed rail securing arrangement for use with concrete sleepers or a permanent way without sleepers, the arrangement comprising a spring clamp, the spring clamp having a shaft extending through an abutment plate and an aperture in the concrete sleeper, or in the permanent way without sleepers, a claw at the leading end of the shaft which positively engages beneath a holding surface in the clamped condition, a spring loop with a holding finger holding down the foot of the rail, either directly or through the abutment plate, and a clamp limit stop bearing on the abutment plate.

2. A rail securing arrangement as claimed in claim 1 wherein the clamp limit stop is constituted by a second spring loop.

3. A rail securing arrangement as claimed in claim 2 wherein the first and second spring loops are differently shaped.

4. A rail securing arrangement as claimed in claim 1, 2 or 3 wherein the claw at the leading end of the shaft, when in the clamped position, is positioned outside the free cross-section of the aperture.

5. A rail securing arrangement as claimed in claim 1, 2, 3 or 4 wherein the holding surface is provided by the undersurface of a holding plate received in the sleeper or in the permanent way.

6. A rail securing arrangement as claimed in claim 4 wherein the holding plate is of helical configuration.

7. A rail securing arrangement as claimed in any preceding claim wherein the aperture is keyhole shaped.

8. A spring-stressed rail securing arrangement substantially as herein described with reference to Figs.1,2 and 4, Fig. 3 or Fig. 5.