EP0401201A1 - Slide chair, slide plate, i. e. tie plate for railway switches or crossings - Google Patents

Abstract

In a slide chair (2), a slide plate or a ribbed plate (1) for rail points or crossings with friction-reducing plastic sliding parts (4, 5) which are removably fixed in recesses (3) of the slide chair (2) or of the plates, at least two sliding parts (4, 5) are accommodated in each recess (3), inward-projecting walls or contoured portions of the edge of the recess (3) engaging over or behind the lateral surfaces of the sliding parts (4, 5) over the majority of their periphery, as a result of which the sliding parts (4, 5) are securely retained while being simple to replace. <IMAGE>

Description

The invention relates to a sliding chair, a sliding plate or ribbed plate for rail switches or crossings with friction-reducing sliding parts made of plastic, which are detachably fixed in recesses in the sliding chair or the plates.

In the case of rail switches with a tongue device, tongue rails rest on sliding chairs and are slidably mounted thereon. In switch constructions in which the switch core itself is pivotally mounted, different constructions are known in which only part of the core is slidably supported on a plate or the entire center is pivotably supported on sliding plates. Swiveling components are also known in the case of rail crossings, with all known constructions having to ensure appropriate lubrication of the bearing or smooth movement of the pivotability on the sliding plates, the sliding chair or the rib plates. Conventional lubrication of the supports results in a high level of maintenance, since the supports have to be supplied with lubricant at regular intervals. Lubricating oils also have the disadvantage that they have different lubricating properties under the influence of the weather and, moreover, that they lose all of their lubricating properties when heavily soiled. For this reason, it has already been proposed to provide friction-reducing plastic sliding parts instead of lubricants. From DE-OS 27 05 122, for example, a switch for rail vehicles with a tongue device has become known, in which the tongue rails rest on sliding chairs, the friction-reducing plastic sliding parts being provided between the parts sliding on one another. With this known construction the plastic sliding parts were provided on the underside of the tongue rails at least in the area of the sliding chairs. In addition, coatings with an organic material have already become known for switch slide plates, plastics of this type being intended to ensure sufficient flexibility, sufficient impact strength and sufficient abrasion resistance even at low temperatures. Plastic sliding parts of this type are also subject to wear, albeit with reduced wear, and therefore require maintenance at certain time intervals. In order to facilitate maintenance work, EP-A 232 726 has already proposed to fix a plurality of sliding elements made of self-lubricating material in a frame which is removably locked in a recess in the sliding chair. As a self-lubricating material, a graphite bronze was proposed for this design, which is used with a tight fit in the frame. The formation of graphite bronze was chosen not least because obviously no formation of sliding inserts was found, which have sufficient stability and can nevertheless be changed quickly and easily without the use of complex tools or equipment.

The invention now aims to provide a sliding chair or a sliding plate or ribbed plate of the type mentioned, which is equipped with friction-reducing sliding parts made of plastic and at the same time offers the secure fixing of the sliding parts with a simple possibility of replacing defective sliding parts. To achieve this object, the design according to the invention essentially consists in that at least two sliding parts are accommodated in each recess, the side faces of which are overlapped or undercut by inwardly projecting walls or profiles of the edge of the recess on the major part of the circumference of the sliding parts. Characterized in that at least two sliding parts are included in each recess, the Side surfaces on the major part of the circumference of the sliding parts are overlapped by rear-engaging walls or profiles of the edge of the recess, on the one hand, the locking walls ensure a secure hold of the sliding parts and, on the other hand, the possibility is created of making the sliding parts simple switch. For this purpose, it is sufficient to lift and pull off one of the two sliding parts contained in the same recess, whereupon the other sliding part can likewise be moved out of the area in which it is overlapped or engaged by inwardly jumping walls or profiles. It is therefore sufficient to design a small part of the circumference of the recess such that it does not overlap the side surfaces of the sliding parts, in order to enable the two parts to be pulled off over this area where the side surfaces are not overlapped, and thereby that the side surfaces on the major part of the circumference of the sliding parts are overlapped or engaged behind by the walls of the recess, a secure locking is ensured in the inserted state without additional measures, in particular without a separate subframe. Furthermore, the arrangement of the sliding parts in the sliding chair, the sliding plate or ribbed plate without the interposition of an auxiliary frame achieves a low overall height, which is particularly advantageous, for example, when using a space-saving inner stock rail bracing.

In a particularly advantageous manner, the design is such that the recesses are elongated and that the parting line of the sliding parts inserted into the recess is arranged transversely to the longer axis of the recess. Characterized in that the recess is elongated, the two sliding parts, which are to be driven into a recess, can be easily driven in the direction of the longitudinal axis of the recess, so that a large area of the circumference is surmounted or recessed by protruding walls or profiles of the edge of the recess, only a relatively short area having to be designed as an exemption in order to be able to lift and pull out the two parts.

The exemption required for lifting or pulling off can be achieved in a simple manner in that the recess has an area with essentially vertical walls, the inside width of which corresponds to the greatest width of the sliding parts transversely to the direction of insertion of the sliding parts. In the area of the essentially vertical walls, dovetail-shaped or trapezoidal-shaped sliding parts can be inserted relatively easily, and driving into the area of the inwardly jumping walls or profiling can take place with a few blows in the longitudinal direction of the recess. Due to the elasticity of the friction-reducing sliding parts made of plastic, there is at the same time a strong prestress towards the bottom of the recess when driving in, so that a secure anchoring takes place at the same time. Since the two sliding parts are driven one after the other, the second driven sliding part snaps in the final phase under elastic pretension towards the bottom of the recess, so that a secure locking against pushing out or escaping of the sliding parts is ensured.

A particularly simple design is obtained if the sliding parts have an essentially trapezoidal cross section and the base angle of the trapezoidal legs corresponds to the associated base angle of the obliquely extending and upwardly projecting walls of the recess. As the base angle of the trapezoidal legs, measured from the bottom of the recess upwards, angles of the order of about 60 ° have proven particularly useful, which on the one hand ensure that there are no great resistances against driving in are, which makes driving the sliding parts easier, and on the other hand ensure a secure fixing of the sliding parts in the recess.

After the two sliding parts have been driven in, a separating joint naturally remains between the two sliding parts, which advantageously runs transversely to the longer axis of the recess in order to provide good support against being pushed out laterally. In this way, the end faces of the sliding parts opposite one another at the parting line form a secure support and counteract any undesired loosening of the sliding parts. In order to prevent the sliding parts from rising, the design is preferably such that the parting line of the sliding parts is arranged in a recess within the region of the recess with essentially vertical walls or close to this region. The distance of the parting line from the clearance defined by the vertical walls must of course be chosen so small that the axial compression of the friction-reducing sliding parts made of plastic when driving in with an appropriate tool, for example a hammer, is sufficient to move the part driven in as the second part the passage through the exemption to expand elastically to such an extent that its end face plunges into an area in which this second sliding part is already overlapped again by inwardly jumping walls. In this way, a particularly high level of security is achieved when locking.

In order to be able to remove unavoidable impurities during operation and thus to counteract premature wear of the sliding elements, the design is advantageously made such that the sliding parts have grooves on their surface which extend in the longitudinal direction of the recess or form an acute angle with the longitudinal direction. The formation of these grooves under pointed Angle to the longitudinal direction of the recess leads here to a lateral wiping off of any dirt particles, so that the slidable friction-reducing surface is only slightly abrasively stressed even in the case of heavy soiling. This advantage arises in particular when the longitudinal axis of the recesses is oriented in the direction of displacement of the movable switch component, in which case, in particular in that the parting line runs essentially transversely and advantageously essentially orthogonally to the longitudinal axis of the recess, possibly in the sliding elements introduced sliding forces can be effectively supported in the area of the parting line without this leading to an increase in the sliding parts.

A particularly high degree of reduction in friction with minimal wear can be achieved by providing two recesses arranged parallel to each other in each sliding chair or each sliding plate or rib plate.

Especially when using an inner stock rail bracing, attention must be paid to low overall heights. When rails or switch parts are fixed in this way, they are generally clamped using leaf wedges using transverse wedges, the sliding chairs having corresponding recesses for the transverse wedges. If for the inclusion of the sliding parts in the recesses overlapping the sliding parts a thicker design of the sliding chair plates is required to securely fix the wedges, the training is advantageously made to compensate for this increase in overall height so that to reduce the overall height for the use of cross wedges tensioned leaf spring elements for the fixing of rails or switch parts, the ribbed plate or base plate below the sliding chair is reduced to a smaller plate thickness is trained. Overall, a reduction in the overall height can be achieved in spite of the slightly protruding sliding parts compared to known designs.

The invention is explained below on the basis of exemplary embodiments shown schematically in the drawing, on the basis of which further advantages of the design according to the invention are illustrated. 1 shows a section through a first embodiment of a ribbed plate according to the invention with a sliding chair with friction-reducing sliding parts; 2 shows a plan view in the direction of arrow II of FIG. 1 on the design according to FIG. 1, FIG. 1 representing a section along the line I-I of FIG. 2; 3 shows an enlarged section of a partial section along the line III-III of Figure 2 by the sliding parts; 4 shows a section similar to FIG. 1 through a modified embodiment; 5 shows a view in the direction of arrow V of the design according to FIG. 4, FIG. 4 showing a section along the line IV-IV of FIG. 5; 6 shows a section through a modified embodiment of a sliding plate according to the invention; 7 shows a view in the direction of arrow VII on the design according to FIG. 6, FIG. 6 showing a section along the line VI-VI in FIG. 7; 8 shows a section through a modified embodiment of a sliding plate according to the invention; and FIG. 9 shows a view in the direction of arrow IX on the design according to FIG. 8, FIG. 8 showing a section along the line VIII-VIII in FIG.

1 to 3, a sliding chair 2 is fixed on a ribbed plate 1, two maintenance-free and self-lubricating sliding parts 4 and 5 made of plastic being arranged in two elongated recesses 3 of the sliding chair. The recesses 3 have an exemption 6 with essentially vertical walls over a limited area, while the recesses 3 have inwardly projecting walls 7 over the remaining circumference, which overlap the side surfaces 8 of the sliding parts 4 and 5 over the major part of the circumference. The sliding parts 4, 5 have an essentially trapezoidal cross-section, as can be seen most clearly from FIG. 3, the angle between the base, that is to say the base surface of the sliding parts resting on the base of the recess 3, and the inwardly projecting legs which Form side surfaces, which essentially corresponds to the upwardly projecting walls 7 of the recesses 3. This angle is designated by α in FIG. 3 and is approximately 60 ° for easy driving in of the sliding parts while ensuring that they are securely anchored in the recesses 3.

The maintenance-free self-lubricating sliding parts 4, 5 made of plastic are of different lengths in the embodiment shown, the length of the individual sliding parts 4, 5 being chosen taking into account the position of the exemption 6 such that both sliding parts 4 and 5 after driving in and anchoring in the recesses 3 are held in their position without additional fasteners. For this purpose, the parting line 10, which runs essentially transversely to the longitudinal direction designated with 9 of the recesses 3, lies between the individual sliding parts 4 and 5 immediately adjacent to the end of the exemption 6, designated with 11, with the essentially vertical walls. During installation, the respectively shorter and 5-labeled sliding part is first inserted into the recesses, whereupon the longer sliding part 4 is inserted via the clearance 6 and has a low axial compressibility which, when driving in, inserts the end 12 of the longer part facing the parting line 10 Sliding parts are allowed in the area of the exemption 6 and, after a corresponding expansion in the inserted position, this end 12 is overlapped to prevent climbing over a short area near the end 11 of the exemption 6, the end area 12 of the sliding parts 5.

In the installed state, the sliding parts 4 and 5 protrude the surface 13 of the sliding chair by a small amount, which is denoted by h in FIGS. 1 and 3. Furthermore, grooves or grooves 14 are provided in the surface of the sliding parts, which in the embodiment shown run at an acute angle relative to the longitudinal axis 9 of the sliding parts 4, 5 or the recess 3 and which are used to remove dirt particles from the surface 15 of the sliding parts 4 and 5 serve. In this way the surface is protected from abrasive influences.

In the embodiment according to FIGS. 4 and 5, a sliding chair 2 is in turn fixed on a ribbed plate 1, whereby sliding parts 4 and 5 made of plastic are in turn accommodated in elongated recesses 3 of the sliding chair. The sliding parts are in turn held over the predominant area of their circumference by inwardly projecting side edges or edges of the recesses 3, as is shown enlarged in FIG. For a particularly low overall height, a lowered region 17 is provided in the base plate 16 of the ribbed plate in the embodiment according to FIGS. 4 and 5, as a result of which a low overall height is achieved, which in particular enables the use of an inner stock rail bracing using extremely low sliding chairs . The offset area 17 at least compensates for any necessary reinforcement of the thickness of the cover plate of the sliding chair for securely receiving the sliding parts 4, 5 and the transverse wedge 20 for fixing.

Due to the direct arrangement of the sliding parts 4, 5 in recesses 3 of the sliding chair and the securing of the sliding parts by reaching over or reaching behind the sliding parts by inwardly jumping wall areas or profiles, the overall height is very low, which, as already mentioned above, results in an inside elastic Attachment of the stock rail is made possible, two different possibilities being shown in FIGS. 1 to 3 and in FIGS. 4 and 5.

6 and 7, 18 designates a sliding plate, wherein in turn elongated recesses 3 sliding parts 4 and 5 are held by inwardly projecting side walls of the recesses. The slide plate 18 is formed with ribs 19, but slide plates without such stops can also be used in a similar manner.

FIGS. 8 and 9 show a modified embodiment of a slide plate 18, which can be used in particular for frog constructions with movable components. These can be frogs with movable wing rails, or frogs with a movable tip, the movable parts resting on the sliding parts 4 and 5 with or without the use of a sliding chair.

The design of the side surfaces of the sliding parts 4 and 5, which have an essentially trapezoidal cross section, and of the inwardly projecting side walls 7 of the recesses 3 is made in essentially the same way as the design shown in FIG. To remove the sliding parts 4 and 5 from the recesses 3, a suitable tool is placed in the parting line 10 and first the sliding part extending over the clearance 6 is levered out and pulled off, whereupon the second sliding part 5 can also be removed from the recess in a simple manner . This results in the possibility of being able to quickly change the sliding parts using the simplest tools, since it is possible to find out what is needed to drive them in, for example with a hammer.

Particularly good sliding properties result from the arrangement of two mutually parallel recesses in a ribbed plate or a sliding chair or a sliding plate, the longitudinal axis of the elongated recesses 3 generally extending in the direction of displacement of the displaceable switch component or crossing part.

The trapezoidal cross-sectional shape of the sliding parts shown in the figures and the side walls of the recesses 3 projecting at an appropriate angle represent a very simple cross-sectional shape that is particularly favorable for the insertion or removal of the sliding parts the side surfaces of the sliding parts are provided, which enable the sliding parts to be securely anchored in the recesses by means of suitable profiles.

Due to the small height of the recesses 3 and the direct insertion of the sliding parts 4 and 5, such sliding parts can be provided practically without increasing the overall height in all conventional ribbed plates with sliding chairs or in sliding plates or sliding plates.

Claims (9)

1. sliding chair (2), sliding plate (18) or ribbed plate (1) for rail switches or crossings with friction-reducing sliding parts (4,5) made of plastic, which are detachably fixed in recesses (3) of the sliding chair or the plates, thereby characterized in that at least two sliding parts (4, 5) are received in each recess (3), the side faces of which on the major part of the circumference of the sliding parts (4, 5) are formed by inwardly projecting walls or profiles (7) of the edge of the recess (3) are attacked or attacked. 2. sliding chair, sliding plate or ribbed plate according to claim 1, characterized in that the recesses (3) are elongated and that the parting line (10) of the inserted into the recess (3) sliding parts (4,5) transverse to the longer axis of the Recess (3) is arranged. 3. sliding chair, sliding plate or ribbed plate according to claim 1 or 2, characterized in that the recess (3) has an area (6) with substantially vertical walls, the inside width of the greatest width of the sliding parts (4,5) transverse to The direction of insertion of the sliding parts (4,5) corresponds. 4. sliding chair, sliding plate or ribbed plate according to claim 1, 2 or 3, characterized in that the sliding parts (4,5) have a substantially trapezoidal cross-section and that the base angle (α) of the trapezoidal legs the associated base angle of the oblique and upward inwardly jumping walls (7) of the recess (3). 5. sliding chair, sliding plate or ribbed plate according to one of claims 1 to 4, characterized in that the joint (10) of the sliding parts (4,5) in a recess (3) within the region (6) of the recess (3) essentially vertical walls or near this area (6) is arranged. 6. sliding chair, sliding plate or ribbed plate according to one of claims 1 to 5, characterized in that the sliding parts (4,5) have on their surface grooves (15) which extend in the longitudinal direction of the recess (3) or with the longitudinal direction enclose an acute angle. 7. sliding chair, sliding plate or ribbed plate according to one of claims 1 to 6, characterized in that the longitudinal axis (9) of the recesses (3) is oriented in the direction of displacement of the displaceable switch component. 8. sliding chair, sliding plate or ribbed plate according to one of claims 1 to 7, characterized in that in each sliding chair (2) or each sliding plate (18) or ribbed plate (1) two mutually parallel recesses (3) are provided. 9. sliding chair, sliding plate or ribbed plate according to one of claims 1 to 8, characterized in that to reduce the overall height for the use of leaf spring elements which can be tensioned by transverse wedges for the fixing of rails or switch parts, the ribbed plate (1) or base plate (16) below of the sliding chair (2) is designed to have a lower plate thickness.

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