Background of the invention Technical area

The invention generally regards a derailer for rail tracks and more specifically a transportable device to prevent rolling stock to get moving in one direction and that in addition is prepared to let rolling stock getting derailed in a controlled way. Prior Art

A buffer stop or a derailer is a device on a rail track that prevent rolling stock that is moving from continuing its movement in the same direction, preventing that free running or unmanned cars to arrive at busy tracks. A rail road track in this connection is a transport rail, also called a vignole rail. A derail device operates so that rolling stock derail when the rolling stock runs over it.

There are different ways to ensure track safety. The most common version is a derail unit is a piece of iron shaped as a wedge that is fastened to and covers the complete top of the rail. If rolling stock hits the derail unit, a flank (an edge on the inside of a railway wheel that allows a wheel axle to stay on the rails all the time) is lifted over the rail and outwards so that the wheel derails. When the derailer no longer is in use, it is swung out and away from the track, so that there is no longer any obstacle on the rail track. This kind of derail unit may be operated manually or remotely. In the first case, it will comprise a connected lock in order to prevent the derail unit to be moved by unauthorized personnel. A big disadvantage with such solutions is that it normally is the left side of the flank on a right side wheel that is used to steer the wheel away, given that the derailing is to happen to the right side. This side of the flank is normally not used in normal railway operations and will not have a suitable surface of contact for the derailing. At high speeds, this results in having little control of what will happen and the security will be a challenging task.

From prior art, reference is made to the patent publication CH 702322 in which is described a mobile derail device comprising a ramp (1 1 ), but this is generally parallel to a rail surface 90 and therefore not arranged to guide a surface of contact vertically upwards. (Claim 1 ) From the prior art, reference is made do the patent publication US 4165060A. In this is described a derail device which is mobile and may be transported from one place to another. It is compact and may be moved by one person. It is intended to prevent rolling stock to move on a railway and also has a ramp (22 in Fig. 3) for guiding the wheel of a railcar up and further on to a derail beam (68 in Fig. 3). This construction uses the flank of the railway wheel to lift the railcar over the railway so that the railcar derails.

Today when work is to be carried out on a section of a railway it is in some countries a requirement, for security reasons, that a length of at least 20 meters of the railway must be removed from each side of the section before the actual work is carried out. This results in considerable cost and loss of time. Provided it can be documented that suitable derail devices can result in the requirements to security can be maintained without removal of railway tracks, such derail devices may replace the solution with removal of railway tracks.

There is a requirement for a mobile derail device that in a controlled way guides pairs of wheels over and away from the railway track. Short description of the invention

A main purpose of the present invention is to bring about a device that is able to derail a railcar when work is done on the railway.

The present invention solves this problem of derailing rolling stock from a railway track in a secure way by lifting both wheels in a pair of wheels so high that the flanks of the wheels reach a height that is higher than the upper part of the railway track. When the pair of wheels are lifted up, the wheels are guided away from the railway track in that at least one of the wheels is guided away from the direction of the railway track.

Summary of the invention

The present invention regards a portable derail device for railway tracks that is arranged to be secured and portably fastened to a single railway track. Further on it comprises a rail ramp, having a top head profile like a normal railway track, such as a Vignoles rail, that is prepared to vertically guide a wheel, on the contact face of the wheel, coming from a railway track and up to an "above rail", so that the guiding flank of the wheel gets positioned above the railway track. This "above rail" has a top head profile like a normal railway track and is arranged to horizontally guide the wheel in an outward pointing arc away from the railway track. This is done with the contact face of the wheel, so that the wheel gets derailed from the railway track. The present invention also regards a system for derailing of rolling stock on railway tracks. A derail device is secured and portably fastened on a right-hand rail and another derail device is secured and portably fastened on a left-hand rail generally parallel to the derail device that is fastened on the right-hand rail. A pair of wheels moving wheels on the railway tracks is with this system prepared first to be lifted up, thereafter to be guided in a direction away from the railway track like in a normal curve, and then be derailed from the railway track.

Short description of the drawings

The invention will now be presented in detail with reference to the drawings in which:

Fig. 1 schematically presents a derail device installed on a railway rail as seen from a side and where a wheel is placed on the rail;

Fig. 2 schematically presents a railway track having derail devices installed on the two rails of the railway track seen above and a pair of wheels placed on the same two rails;

Fig. 3 schematically presents the same as in Fig. 1 , but here with the wheel at the top of a rail ramp and at the start of an "above rail";

Fig. 4 schematically presents the same as in Fig. 2, but here with the wheels at the top of the rail ramps and at the start of "above rails";

Fig. 5 schematically presents the same as in Fig. 3, but here with the wheel at the end of the "above rail" and in the position where the derailing of the wheel is about to be completed;

Fig. 6 schematically presents the same as in Fig. 4, but here with the wheels at the end of "over rails" and in a position where the derailing of the pair of wheels is about to be completed;

Fig. 7 schematically presents the same as in Fig. 5, but here with the wheel on the outside of the "over rail" and the railway rail after that the derailing is completed;

Fig. 8 schematically presents the same as in Fig. 6, but here with the wheels on the outside of the "over rails" and the railway rails after the derailing of the wheels is completed; and

Fig. 9 schematically presents a front view of a cross section of a derailing unit installed on a rail and with a wheel positioned on the "over rail". Reference numbers as used in the drawings:

Detailed description of the invention

The invention will now be described in more detail with reference to the drawings.

In Figs. 1 , 3, 5 and 7, just the right rail is illustrated, and derailing of rolling stock comprising wheel 300 from the rail is configured by means of installed derail device 100 where moving of the wheel 300 is from right to left in the drawings.

In Figs. 2, 4, 6 and 8, a railway track with two rails 200 is illustrated, and a system for derailing of rolling stock comprising pairs of wheels having wheel 300 and is configured with two derail devices 100 in which the movement of the pair of wheels is from left to right in the drawings.

In Fig. 9, just the right rail 200 (referred to the direction of movement) illustrated together with a right wheel 300 upon an "over rail" 120 so that the whole of the wheel 300 is higher than the upper surface of the rail 200.

In a preferred embodiment, the invention may be described as follows with reference first to Fig. 1 . In this drawing, the derail device 100 of the present invention is installed on a rail 200 of a railway track. The derail device 100 is here fixed onto a rail web 210 of the rail 200 with 8 fastening bolts 140 and with an inside fastening part 141 between the fastening bolts 140 and the rail web 210. Integrated in the derail device 100 is a rail ramp 130 and an "over rail" comprising a guiding flank 120, here also just called "over rail" 120.

When rolling stock, e.g. a goods wagon comprising a pair of wheels 300, moves from the right in Fig. 1 , the wheel 300 will, as time goes on, arrive at the rail ramp 130 which is part of the derail device 100. This ramp 130 will press the wheel 300 vertically upwards and further onto the "over rail" 120. The ramp 130 has a height that ensures that the outer diameter of the wheel 300, which is constituted by the wheel flank 310 of the wheel 300, gets at least as high as the "over rail" 120 when the rail ramp 130 gets passed. This is presented in Fig. 3. Both the rail ramp 130 and the "over rail" 120 has a design and a contact area similar to a railway rail 200. The "over rail" is curved horizontally in order to guide the wheel 300 to the side of the rail 200 similar to in a normal curve of a normal railway rail 200. It may in addition have a flank guide ensuring that the wheel flank 310 is guided in the same direction as the "over rail" 120. The height of the "over rail" 120 above the railway rail 200 ensures that the whole of the wheel 300 can pass unhindered over the railway rail 200. Another preferred embodiment of the invention is a system in which derail devices 100 are installed in parallel, one on each of right and left rails 200 respectively.

Because there are two derail devices 100 installed generally in parallel in this embodiment, both right wheel 300 and left wheel 300 in the pair of wheels are lifted vertically and generally at the same time and the horizontal support from left and right railway rails 200 are taken over by the rail ramps 130 and then the "over rails" 120. In Fig. 9 is presented a right wheel 300 positioned on the "over rail" 120 seen against the direction of movement. Because the derailing in this embodiment is planned towards the right in the direction of movement, this wheel 300 will travel in an inner curve and consequently the other, i.e. the left derail device 100 will receive the major horizontal forces from the rolling stock that is to be derailed, so that the rolling stock is turned towards the right side. The invention in other words utilizes the mechanisms that already is part of ordinary railway operations. The surfaces of contact of the wheels 300 towards the railway rails 200 are the whole time, until the wheels 300 leave the derail devices 100, similar to when they roll on railway rails 200. Depending on speed, weight and turning radius, the forces involved can nevertheless turn larger than in ordinary service, but the underlying forces and the material used are known. Values of acceptable limits in use can therefore straightforwardly be calculated.

In an alternative embodiment, a vertical sleeper support 150 bear against a sleeper underneath the rail 200. This can have a preferred surface of contact against the sleeper so that the point load between the sleeper support 150 and the sleeper is not higher than desirable. The advantage with this sleeper support 150 is that the derail device 100 is getting an enforced anchoring against horizontal movement. In order to simplify, all drawings and embodiments are describing derail devices 100 only describe rolling stock being derailed towards right in the direction of movement. Alternative embodiments for the derail device 100 according to the present invention and that are to derail towards the left direction will of course only have to have the "over rail" 120 to be manufactured with the direction of curve to the left instead of to the right. This regards all the above embodiments.

A great advantage of the present invention is that the construction is suited to be adapted to different requirements for the derail device 100. Dimensions and angles can be adapted to heavy rolling stock in great speed. The weight of the equipment consequently be higher and more demanding to transport and install, but on the other hand one can also produce lighter derail devices in cases for which the requirements are less demanding than normally. A derail device 100 for rolling stock of up to 40 tons and having a speed of up to 40 kilometers per hour can for instance easily be carried by two men.

The derail device 100 according to the present invention is designed for a planned maximal strain. Above such a strain, construction material may deform or cracks may develop. The derail device 100 may nevertheless have performed its task, but maybe it has to be replaced. Many times, the real strain that has occurred in an accident may be difficult to decide afterwards, so that the derail device 100 may have to be required to go through a certification procedure in order to be accepted for use again after having been used just once. Alternative it may be scrapped after having been run over. Moving and placement of the derail device 100 can be done simply by two persons in that there may be provided lifting handles at the ends of the derail device 100. Such handles are not shown in the drawings. Reference is now made to Fig. 9 for describing how the derail device 100 may be installed. We have as starting point a derail device 100 that derail to the right in the direction of movement. Right and left in this description relates all the time in the present description and will therefore in Fig. 9 be shown opposite so that e.g. right hand fastening bolts 140 are seen on the left side of Fig. 9. Further on, the first fastening bolt 140 is the one that is positioned furthest backwards in the direction of movement. A derail device 100 can easily be installed by lowering it downwards onto a rail of a railway rail 200 at the position it is desirable to install it and with the sleeper support 150, positioned in an elongated position relative to an outside fastening part 142, generally against the sleeper. Thereafter, the first left fastening bolt 140 is screwed towards the rail web 210 so that an inside fastening part 141 gets positioned tightly against the head of the railway rail 200. It may be

advantageous to place support elements between the fastening bolts 140 and the rail web in order to ensure an even pressure and to increase friction. Such support elements can be observed in Fig. 9, but without any reference number. Thereafter, the first right hand fastening bolt may be fastened by screwing. The derail device 10 should all the time during the installation be pressed against the railway rail 200. The inside fastening part 141 safeguards a correct horizontal placement on the railway rail 200. The fastening bolts 140 are typically to be screwed on the right side through threads in the outside fastening part 142 and further through spacious holes in the inside fastening part 141 and further to the rail web 210. On the left side, the fastening bolts 140 are to be screwed through threads in a side support 1 10 and further towards the rail web 210.

In the present invention railway rail, rail, transport rail and vignole rail are used for the same unit 200.