AU562566B2

AU562566B2 - Means for fastening a rail to a sleeper

Info

Publication number: AU562566B2
Application number: AU29659/84A
Authority: AU
Inventors: R. Johde
Original assignee: Fiskars Oyj Abp
Current assignee: Fiskars Oyj Abp
Priority date: 1983-05-30
Filing date: 1984-05-29
Publication date: 1987-06-11
Anticipated expiration: 2004-05-29
Also published as: FI72776B; IT8421144A1; GB8515422D0; ZA844059B; SU1421262A3; ATA906784A; EP0178301A1; ES288818U; ES288818Y; SE8505619D0; GB2158859B; FI831935A0; GB2158859A; AT384635B; KR850001347A; DK39285A; JPS60501464A; EP0178301B1; IT1174562B; SE8505619L

Description

Means for fastening a rail to a sleeper

The present invention relates to means for faste¬ ning a rail to a sleeper, comprising a steel spring of the general shape of the letter M, with its central part abutting against a rigid support, from the rail side, and with its branches extending onto the rail foot (base) .

A rail fastening means of this kind is disclosed in the Finnish patent no. 53 336, in addition towhich a plurality of other structures are known, which comprise aresilient spring member to be tensioned between a rigid support and the rail foot. These prior structures have in common that the elastic spring member is only used for pressing the rail foot against the sleeper and additipnal means are used for supporting the rail lateral¬ ly. The prior rail fasteners are therefore comparatively complicated and expensive.

It is the object of the invention to provide a new rail fastener which is of simpler structure than the prior fasteners.

The rail fastener according to the invention is mainly characterized in that the surface of the spring branches acting on the rail foot ends in a shoulder which limits the lateral movement of the rail. According to the invention the resiliency of the spring is thus used both for pressing the rail against the sleeper and for supporting the rail laterally.

In a preferred embodiment of the invention, the cross section of the spring is of rectangular shape, and it is further preferable to arrange the central part of the spring to extend close to the rail foot, the distance being approximately two to three millimetres. Thus formed, the central part of the spring provides a secondary or reserve lateral support for the rail, for the case that either or even both M-branches slip due to deformation or any other reason, e.g. loosening of the anchoring

OMPI element.

The invention will in the following be described in more detail, with reference to the accompanying draw¬ ing. Figures 1 and 2 show the rail fastener as mounted on one side of a rail, seen from above and as a partial cross section, respectively.

Figures 3 and 4 show the spring seen from the side and from above. The rail to be fastened, of which a part only is visible in figures 1 and 2, is denoted by reference nume¬ ral 1 and its foot or base by numeral 2. 3 denotes a sleeper made of e.g. concrete, and 4 denotes a resilient sheet larger between the rail foot and the sleeper. in the sleeper is rigidly anchored a screw 5 which by means for a shoulder or flange 6 tensions a resilient spring member 7 against the rail foot 2. The spring is preferably formed of a steel bar bent to the general shape of the letter M (or ) . The central part 8 of the spring 7 runs between the rail foot 2 and the screw 5 whereas the screw provides a stop for the spring in the direction away from the rail, and the ends of the spring branches extend onto the rail foot 2 and press the latter against the sheet layer 4 and sleeper 3. in addition to pressing the rail foot against the sleeper, the spring 7 also limits the latual movement of the rail by means for a shoulder 14 formed in the surface 13 pressing against the rail foot, in each of the M-branch- es 10 and 11. Since there is one shoulder 14 on each side of the central part 8 of the spring held by the screw 5, ^' the spring 7 will not turn and the screw prevents the spring form yielding laterally more than what is permitted by the resiliency of the areas between the branches 9 and 10. The rail fastening arrangement here suggested has the major advantage of being very simple in structure and

OMPI thus of being cheap, and this is accomplished by using the resiliency of the spring 7 both for pressing the rail foot against the sleeper and for supporting the rail laterally. Under so-called normal conditions the shoulders 14 of the two spring branches 9 and 10 provide the necess¬ ary lateral support. However, one can expect that either the screw 5 may loosen or the spring 7 may be deformed, due e.g. to a difficult climate with severe winters, whereupon either of or both shoulders 14 may slip or yield too much. To encounter this it is preferably to have a spring of rectangular cross-section and to have the cent¬ ral part 8 of the spring to run at a close distance, e.g. 2 to 3 mm, to the edge of the rail foot. Thus the central part 8 of the spring 7 provides an efficient reserve late- ral support for the rail. For so-called normal conditions, the spring 7 may as well be of circular cross-section, which saves some material over a rectangular cross section, - but on the other hand a spring of rectangular cross section is easier to manufactureand providesamore efficient se- condary lateral support.

As shown in figures 1 and 2, a packing 15 may be placed under the central part 8 of the spring 7, and a further resilient intermediate packing, e.g. in one piece with the sheet layer 4, may still be positioned underneath the packing 15.

The invention is not restricted to embodiment of the drawing only. The spring 7 need not be planar as seen from the side, and the branches of the spring may extend longer onto the rail foot. Another rail fastener is of course arranged at the other side of the rail.

Claims

Claims :

1. Means for fastening a rail to a sleeper, inclu¬ ding a spring (7) having the general shape of the letter M, the central part (8) of which is arranged to form the rail side abut a support anchored in the sleeper and the branches of which are arranged to extend onto the foot (2) of the rail (1), c h a r a c t e r i z e d in that the surface (13) of each spring branch (9, 10) acting on the rail foot (2) ends in a shoulder (14) limiting the lateral movement of the rail (1).

2. Means according to claim 1, c h a r a c t e ¬ r i z e d in that the central part (8) of the spring (7) is arranged to run close to the edge of the rail foot (2) and that the spring has a rectangular cross section.

3. Means according to claim 1 or claim 2, c h a ¬ r a c t e r i z e d in that between the central part (8) of the spring (7) and the sleeper (3) is arranged a pack¬ ing (15) , and that between the rail and the sleeper is arranged a resilient sheet layer (4) extending underneath said packing (15).

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