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(11) | EP 1 125 815 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Sealing arrangement for a sliding cover in a railway freight wagon |
| (57) The invention relates to a sealing arrangement for the edges of a sliding cover (10)
in a railway freight wagon, comprising an edge sealing (2) of elastic material, which
is substantially C-shaped in cross-section and has the ends of its legs (4, 5) provided
with engagement bosses (3). The vicinities of cover edges (1a, 1b, 1c, 1d) include
two broached-bottom mating grooves (6) at a distance (W1) from each other for receiving
the engagement bosses (3) of an edge sealing, whereby the edge sealing is in contact
with the cover. The edge sealing has a central portion (7) of its C-profile compress
against a wagon frame (9) while the cover is in a closed position (S). As the shape
of a wagon frame changes during running, for example, the central portion rolls along
the surface of a mating structure, thus reducing wear and tear. |
[0001] The invention relates to a sealing arrangement for the edge of a movable cover in a railway freight wagon, comprising an edge sealing of an elastic material, which is substantially C-shaped in cross-section and disposed along the edge portions of the cover between the cover and a fixed freight wagon frame.
[0002] In most cases, the sealing in a railway freight wagon between a sliding cover, which in this context refers to sliding walls and sliding roofs, and a freight-wagon undercarriage or other fixed structural elements is taken care of by means of a labyrinth sealing, which extends along the edges of a cover and consists of specially designed edge portions for the cover and matching specially designed counterparts for the undercarriage or a fixed element. Labyrinth sealing is based on subjecting an air flow external of the wagon, which strives to pass through the sealing as a road draft, to a number of powerful deflections and on having gaps as small as possible between the inelastic edge portions and the inelastic counterparts. Such labyrinth sealing requires a high precision of manufacture, and the cover becoming battered or the like results either in considerable leaks or in the cover not closing properly. Even if a labyrinth sealing were to provide a satisfactory function in more conventional conditions, it is particularly easy, a labyrinth sealing notwithstanding, for subzero snow to work its way inside a freight wagon, which is not desirable.
[0003] Publication DE-41,29,480 Al discloses a supplementary seal for labyrinth sealing, comprising an elastic sealing profile with a roughly C-shaped cross-section, even though this is not defined in the cited publication. The C-profile sealing is secured in the middle with screws to a labyrinth groove in the central arch and the gable of a freight wagon, whereby the lips of the profile remain free and point towards each other at a distance from the bottom of the labyrinth groove. In the process of closing the cover, the sliding wall has its protruding band moving in between the lips of the C-profile sealing and setting itself against a wearing strip present upon the internal bottom of the C-profile sealing. True enough, this does improve the applicability of a labyrinth sealing, but the described sealing solution is only suitable for use in junctions extending crosswise of a freight wagon. The sealing solution described in the cited publication cannot be used for sealing the bottom edge of a cover at the level of a wagon floor, nor for a sealing between the top edge of a cover and the central beam since, at these locations, the packing or sealing sets in a horizontal position, resulting in the accumulation of water, which in itself causes a corrosion hazard. In addition, the water accumulated in a sealing may freeze, which prevents the cover from being opened and/or closed.
[0004] It is an object of the invention to provide such a sealing arrangement for a sliding cover in a railway freight wagon, which is suitable for use at all edges of the cover, preferably unaltered or with no more than minor alterations. A second object of the invention is a sealing arrangement of the above type, which would have an excellent tightness in all sorts of ambient conditions, such as in a snowfall and/or with the temperature fluctuating on either side of 0 °C. A third object of the invention is a sealing arrangement of this type, which would neither, at least not easily, lose its tightness as a result of unintentional deformations possibly occurring as the cover is used. A fourth object of the invention is a sealing arrangement of the above type, which, in order to achieve tightness, does not require particularly high precision regarding the dimensions of an entire cover and, thus, the area of sealing, or, alternatively, does not require a cover-specific finishing for the area of sealing. A fifth object of the invention is a sealing arrangement of the above type, which would be simple and expedient to assemble. Yet another object of the invention is a sealing arrangement of the above type, whose maintenance or, if necessary, repair, i.e. a restitution of tightness in case the sealing is damaged for some reason, would be as expedient and convenient as possible.
[0005] The above problems can be resolved and the above objects can be achieved by means of a cover structure of the invention, which is characterized by what is defined in the characterizing clause of claim 1.
[0006] The most significant benefit gained by the invention is that the inventive transferable cover, such as a sliding roof or a sliding wall, extending both to the height of a freight wagon wall and roughly to the half-width of a freight wagon roof, as well as over a substantial portion of a freight wagon length, can be provided with an excellent tightness, even if the manufacture of the cover edge portions is carried out with just conventional precision or even with low-level precision, in other words, the inventive sealing arrangement enables the edges of a cover and the sealed portions of a freight wagon undercarriage to tolerate dimensional variations more prominent than those permitted by the prior known solutions. This relatively extensive dimensional fluctuation afforded by a sealing arrangement of the invention also prevents the sealing e.g. from developing a leak, even if the cover, for example, had been handled improperly, resulting in a slight change of its shape. Furthermore, the inventive sealing arrangement enables a highly expedient installation thereof and, if necessary, an expedient and easy replacement with another, even in difficult conditions and without special tools.
[0008] Fig. 1 shows in a lateral view and generally a typical railway freight wagon, which is provided with a sliding cover sealed with a sealing arrangement of the invention, in this case a sliding wall extending roughly to the extent of a half-length of the wagon.
[0009] Fig. 2A shows a sealing arrangement of the invention at a sealing between a sliding cover and the gable of a freight wagon, with the cover in a closed position S and in an open position A, in a more or less horizontal cross-section along a plane A-A in fig. 1.
[0010] Fig. 2B shows a sealing arrangement of the invention at a sealing between a sliding cover and the central arch of a freight wagon, with the cover in a closed position S and in an open position A, in a more or less horizontal cross-section along a plane B-B in fig. 1.
[0011] Fig. 2C shows a sealing arrangement of the invention at a sealing between a sliding cover and the floor of a freight wagon, with the cover in a closed position S and in an open position A, in a vertical cross-section along a plane C-C in fig. 1.
[0012] Fig. 2D shows a sealing arrangement of the invention at a sealing between a sliding cover and the top beam of a freight wagon, with the cover in a closed position S and in an open position A, in a vertical cross-section along a plane D-D in fig. 1.
[0013] Fig. 3 shows a detail for an engagement between a sealing of the invention and a cover, in a view similar to figs. 2A-2D, but in a larger scale, from a point I in fig. 2B.
[0014] The invention relates to a sealing arrangement for all edges 1a, 1b, 1c, 1d of a movable cover 10 in a railway freight wagon, comprising, as a principal sealing, an edge sealing 2 of an elastic material. The cover of a railway wagon, such as a sliding roof or a sliding wall, thus comprises bulky movable cover element, which constitutes the principal section of both a wall and a roof for the wagon and has a length which is typically about a half of the length of the covered section of a freight wagon, as can be appreciated from fig. 1. The movable or transferable cover 10 is opened by moving it in a direction opposite to closing movement M, that is outwards from interior of the wagon and transferred e.g. on rollers or other type of transfer means in the longitudinal direction of the wagon over and outside the closed cover section(s), and closed by transferring in the longitudinal direction of the wagon until on the area of the respective loading opening and followed by the closing movement M towards the interior of the wagon. The means or components for transferring the sliding cover can be of any type known as such or new, and are so not described in this text. In these cases, all dimensions of a cover are typically several meters. There is nothing to stop the use of a sealing arrangement of the invention also in a shorter sliding cover, such as in a cover element, which extends more or less to a third or the like of the wagon length. This edge sealing is essentially C-shaped in cross-section, at least when installed in its position along the cover 10 and with the cover in its open position A. The C-shaped edge sealing 2 is set to extend along the edge portions of the cover 10, as well as between the cover and a fixed freight wagon frame 9. According to the invention, said C-shaped edge sealing 2 has the ends of its legs 4, 5 provided with engagement bosses 3 extending lengthwise of the sealing. The sliding cover 10 has the vicinities of its edges 1a, 1b, 1c, 1d provided with two broached-bottom mating grooves 6 at a distance W1 from each other for receiving the engagement bosses 3 of an edge sealing in a direction La, Lb, Lc, Ld of said grooves, whereby the edge sealing 2 attaches in a sealed fashion to the cover 10. The direction of said grooves is the same as a lengthwise direction La, Lb, Lc, Ld for each section of the edge sealing 2. The C-shape of the edge sealing 2 has such a circumferential length that the C-shape has a maximum width W2, which exceeds the distance W1 between the mating grooves 6 in the direction of this distance. The broached bottom of the mating grooves 6 has a lateral dimension D2 and the engagement boss 3 has a lateral dimension D1, both of which exceed substantially a width P2 across a lengthwise slot 17 in the mating grooves, such that under no circumstances is the engagement boss 3 able to slip out of the mating groove 6 through the lengthwise slot 17, i.e. with respect to a surface 11 existing at this point seen in lateral direction, as well as with respect to the distance W1 between the mating grooves. Respectively, the lateral dimensions D1, D2 of the engagement boss and the mating groove exceed substantially a material thickness P1 of the legs 5, 6 of the C-profile. In the open position A of a cover, the edge sealings 2 are completely disengaged from the support thereof, to be described subsequently in this specification, and this sliding cover 10 is in a position transferred across the top of another cover, which is in the closed position S, this being a conventional mode of transfer for sliding covers and, therefore, not described in more detail in this specification. The edge sealing 2 has between its legs 4, 5 a central area 7 for the C-profile, which is pressed against the fixed frame 9 as the cover is carried in a direction M to the closed position S and causes sealing of the cover on the undercarriage of a wagon against said supports, or on another cover against supports included therein while it remains in this closed position S.
[0015] The lengthwise engagement bosses 3 of the edge sealing 2 are essentially circular in cross-section, each having a substantially equal lateral dimension or diameter D1, and the mating grooves 6 therefor in the cover are also essentially circular in cross-section, each having a substantially equal lateral dimension or diameter D2. It is beneficial that the engagement boss 3 and its mating groove 6 be given a round or circular cross-section, since, thereby, the insertion of two engagement bosses of an edge sealing present at the extreme ends of its legs 4, 5 during installation of the sealing 2 in the lengthwise direction La, Lb, Lc, Ld of the mating grooves can be managed without problems. After all, these mating grooves and, thus, the edge sealings 2 engaged therein do have a remarkable length to match at least the length of cover edges la, 2b, lc, 1d, the mating grooves and sealings being present within the confines or vicinity of said edges, as well as extending parallel thereto. In order to further facilitate the installation of edge sealings, the lateral dimension D1 of the engagement boss 3 is smaller than the lateral dimension D2 of the mating groove 6 by a first clearance V1, i.e. V1 = [D2-D1]/2. Likewise, the material thickness P1 of the edge sealing legs 4, 5 is smaller than a width P2 of the lengthwise slot 17 in the mating groove by a second clearance V2, i.e. V2 = [P2-P1]/2. The clearances V1 and V2 can be equal or unequal in size and in the order of 0,2 mm - 1 mm. The engagement bosses 3 and, respectively, the mating grooves 6 therefor may also be somewhat elliptical or angular in cross-section, as long as there are sufficient roundings in both cases and the aspect ratio, i.e. the ratio between the width of a cover parallel to the surface 11 and the height orthogonal thereto, does not deviate too much from the value 1:1, the potential range of fluctuation being possibly within the range of 0,5:1 - 1:0,5 or more preferably within the range of 0,7:1 - 1:0,7. The edge sealing 2, i.e. its C-profile, has in the most preferred case a cross-section which is either essentially circular or elliptical, whereby it has a maximum width W2 which substantially exceeds the distances W1 between the mating grooves, and a total height H which, of course in a non-compressed state of the sealing, in a direction perpendicular to the distance W1 between the mating grooves, is in the same order as the maximum width W2 of the C-profile, which affords a sufficient elasticity for the sealing.
[0016] With regard to other dimensions of the sealing arrangement, it can be pointed out that the lateral dimensions D1, D2 of an engagement boss and a mating groove, respectively, can be within the range of 1,5 mm - 7 mm, the distance W1 between the mating grooves 6 for example within the range of 10 mm - 40 mm, and the maximum width W2, as well as the maximum height H, of the C-profile of the edge sealing 2, as the sealing is fitted in the mating grooves in a free state, i.e. not compressed against the sealing, exceeding the distance W1 between the mating grooves by 5 mm - 15 mm.
[0017] The above described sealing design is capable of providing an excellent durability for a sealing since, with the undercarriage or fixed frame 9 of a wagon springing, the central portion 7 of the inventive edge sealing 2 has its peripheral surface rolling, although slightly flattened from a circle or some other corresponding convex rest form thereof, as shown in the figures, along the surface of the fixed frame in a direction transverse to the lengthwise direction La, Lb, Lc, Ld of the sealing. This can be clearly appreciated for example in the case of fig. 2C as a railway wagon floor 12 springs slightly up and down in directions T, the central portion 7 of a sealing rolling back and forth along a rim surface 19 of the floor. The material for an edge sealing of the invention comprises some suitable grade rubber or another appropriate elastomer.
[0018] As mentioned above, the mating grooves 6 and the edge sealings 2 inserted therein circulate along the vicinities of all the edges la, 1b, 1c, 1d of a cover. The distance W1 between the mating grooves is essentially parallel to the surface 11 of the cover 10. The central portion 7 of a C-profile located at least roughly opposite to said distance W1 of the edge sealing 2 compresses, during the movement of a cover to its closed position S, at the bottom edge lc of a cover against the side edge of a freight wagon floor 12, at the ends 1a, 1b of a cover against the bottom of a freight wagon gable 13 and, respectively, the bottom of a gutter 8a, 8b in the central arch 14, as well as at the top edge 1d of a cover against the top surface of a lengthwise strip section 16 in a central beam 15.
[0019] At corner points 22a, 22b, 22c, 22d for the edges 1a, 1b, 1c, 1d of the cover 10, the edge sealings 2 can be arranged as extensions of each other either with a per se known unbonded mitre box joint, wherein the edge sealings form 45° relative to the length of the sealings, and the sealings have bevelled ends thereof set against each other, or with a bonded mitre box joint, wherein the sealings 2 have cross-sectional surfaces thereof further bonded together with an adhesive. If the lengths of the sealings do not coincide with each other perpendicularly, the edge sealings have mitre corners thereof dimensioned accordingly. Alternatively, the edge sealings 2 of various edges 1a, 1b, 1c, 1d can be arranged at the edge corner points of the cover 10 as extensions of each other by fitting the corner points 22a, 22b, 22c, 22d with separate corner pieces or gussets made, for example, in cast aluminium or manufactured in some other way, which include arcuate mating grooves and which are mounted on the cover in such a way that the mating grooves 6 continue from one edge of the cover to the next edge of the cover in a stepless fashion by way of the arcuate groove present in the gussets. Consequently, the edge sealing 2 can be placed in its position by pushing and/or pulling along its mating grooves and along the arcuate mating grooves without the necessity of, cutting it at comer points. Optimally, the edge sealing for all edges 1a, 1b, 1c, 1d of a single cover consists of a single continuous edge-sealing element. This continuity is rendered possible by the above-described first and second clearance V1, V2, as well as by said gusset at the corners of a cover. Of course, at some point of the cover edges there must be an appropriately designed spot enabling the pushing and/or pulling of an edge sealing into its mating grooves. When using the last-described type of gussets, the edge sealing can be set in its position not only as a single continuous element but also, for example, in the way of two elements, whereby each cover - for example the top corners 22a and 22b - can be provided with two gussets and other parts thereof - for example the bottom corners 22c and 22d - are provided with a mitre box joint. The sealing has one, two, or possibly three of its extensions or splices positioned at such points/such a point or at such corners/such a corner of the cover edges, wherein the tightness of a splice is most securely achieved or wherein a possible minor leak is least harmful.
1. A sealing arrangement for edges (1a, 1b, 1c, 1d) of a movable cover (10) in a railway
freight wagon, comprising an edge sealing (2) of an elastic material, which is substantially
C-shaped in cross-section and disposed along the edge portions of the cover (10) between
the cover and a fixed freight wagon frame (9), characterized in that said C-shaped edge sealing (2) has the ends of its legs (4, 5) provided with
engagement bosses (3) extending lengthwise of the sealing, and the sliding cover (10)
has the vicinities of its edges (1a, 1b, 1c, 1d) provided with two broached-bottom
mating grooves (6) at a distance (W1) from each other for receiving the engagement
bosses (3) of the edge sealing in a direction (La, Lb, Lc, Ld) of said grooves, whereby
the edge sealing (2) attaches in a sealed fashion to the cover (10); and that the
sealing of a cover is accomplished by the compression of a central portion (7) in
the C-profile of the edge sealing (2) against the fixed wagon frame (9) while the
cover is in a closed position (S).
2. A sealing arrangement as set forth in claim 1, characterized in that the lengthwise engagement bosses (3) of an edge sealing are substantially
circular in cross-section and the mating grooves (6) therefor in a cover are substantially
circular in cross-section; and that the broached bottom of the mating grooves (6)
has a lateral dimension (D2) and the engagement boss (3) has a lateral dimension (D1)
which both exceed substantially a width (P2) exhibited by a lengthwise slot (17) of
the mating groove.
3. A sealing arrangement as set forth in claim 2, characterized in that the lateral dimension (D1) for the engagement boss (3) of an edge sealing
is smaller by a clearance than the lateral dimension (D2) for the mating groove (6),
and the legs (4, 5) have a thickness (P1) which is smaller by a clearance than the
width (P2) of the lengthwise slot (17) in the mating groove.
4. A sealing arrangement as set forth in any of the preceding claims, characterized in that said mating grooves (6) and the edge sealings (2) inserted therein circulate
along the vicinities of all the edges (1a, 1b, 1c, 1d) of a cover; and that the distance
(W1) between the mating grooves is substantially parallel to a surface (11) of the
cover (10).
5. A sealing arrangement as set forth in claim 1, characterized in that the edge sealing (2) has the central portion (7) of its C-profile compressed
at the bottom edge (1c) of the cover against the side edge of a freight wagon floor
(12), at the ends (1a, 1b) of the cover against the bottom of a freight wagon gable
(13) and, respectively, the bottom of a gutter (8a, 8b) in a central arch (14), as
well as at the top edge (1d) of the cover against the top surface of a lengthwise
strip section (16) in a central beam (15).