GB2547639B

GB2547639B - Changeover assisting apparatus for a railway points adjusting device

Info

Publication number: GB2547639B
Application number: GB1602842.5A
Authority: GB
Inventors: Walter Daniel; Meyer Frank
Original assignee: Schwihag AG
Current assignee: Schwihag AG
Priority date: 2016-02-17
Filing date: 2016-02-17
Publication date: 2019-09-04
Anticipated expiration: 2036-02-17
Also published as: GB201602842D0; GB2547639A

Description

CHANGEOVER ASSISTING APPARATUS FOR A RAILWAY POINTS

ADJUSTING DEVICE

The present invention relates to changeover assisting apparatus for a setting or an adjusting device of a set of railway points and to an arrangement composed of such apparatus and a rail bedplate on which the apparatus is mounted.

Changeover assisting apparatus for setting devices or for points locking devices of railway points are well-known from the prior art. The setting devices are provided to actuate switchblade devices substantially consisting of two stock rails and two associated movable tongue rails, wherein the tongue rails can be moved by means of the setting devices between two points positions, namely an open tongue rail position and a closed tongue rail position.

At, in particular, larger sets of points, a number of such setting devices is provided for this purpose, wherein these are usually connected together by means of appropriately constructed points operating linkages.

Such linkages frequently extend parallel to the respective set of points.

The changeover assisting apparatus in this case comprises at least one bellcrank lever which is connected by means of the points operating linkage with the respective setting devices, usually two setting devices.

The bellcrank lever is rotatably mounted on a vertically aligned axle, which is screwed by means of an axle base plate onto a steel intermediate plate which is in turn fastened to a railway sleeper. The axle is in this case fixed on the base plate by means of a pin so as to be secure against twisting.

The base plate is in turn connected by means of the intermediate plate with a rail bedplate on which a rail rests. The intermediate plate here forms the actual connecting part between the base plate of the changeover assisting apparatus and the bedplate, so that the apparatus is arranged adjacent to the bedplate.

In order to facilitate assembly on site at a railway line or set of railway points, the axle base plate and the rail bedplate are each connected with the intermediate plate by means of a screw connection. A disadvantage of these screw connections is that critical relative movements repeatedly occur between the three components of intermediate plate, rail bedplate and axle base plate, with the result that the functionality of the changeover assisting apparatus is frequently detrimentally affected in such a way as to lead to malfunctioning of the railway points.

In addition, these undesired relative movements result not only in faults at the setting devices, but also in increased wear of the vertically extending axle of the bellcrank lever.

Further, the changeover assisting apparatus has the disadvantage that the pin connection between the vertically aligned axle and the axle base plate is frequently too weak to be able to absorb the forces which occur due to the undesired relative movements, so that the pin connecting the axle and the base plate can shear off completely in the most unfavourable case, as a consequence of which the axle is no longer fastened to the base plate to be secure against relative rotation.

Moreover, the bellcrank lever of the changeover assisting apparatus is secured against unintentional lifting from the vertically aligned axle only by a simple split pin, so that functional failure of the apparatus can also arise if the split pin breaks or is lost.

The invention has the object of developing changeover assisting apparatus so that at least the aforesaid disadvantages can be overcome.

According to one aspect of the present invention there is provided an arrangement comprising a rail bedplate and changeover assisting apparatus, the apparatus being mounted on the bedplate, wherein changeover assisting apparatus comprises a bellcrank lever to which points operating linkages of adjusting devices of a set of railway points are coupleable and an axle element on which the lever is mounted to be pivotable about an axis of rotation, wherein the axle element has a foot formed so that the axle element is fitted by means of the foot in a receptacle of substantially complementary form in the rail bedplate to be secure against rotation relative to the bedplate and to extend substantially vertically in use of the bedplate so that the axis of rotation is substantially vertical.

Since the axle element is configured in part as a foot, the previously required axle base plate and the disadvantageous pin connection between the element and the plate can be dispensed with, so that as a result the risk of functional failure with respect thereto is eliminated.

Moreover, the previously essential intermediate plate can also be dispensed with, since the axle element can be arranged by its foot mechanically positively and directly in the bedplate receptacle formed to be complementary to this foot.

In other words, the axle element can be fastened directly to the bedplate, thus bypassing the previously required intermediate plate or other such component.

The axle element can be designed in various ways. It preferably comprises an elongate body extending in the direction of the axis of rotation. The base body is preferably made of a solid material, but can also be a tube.

As a result of the mechanically positive or shape-locking/interlocking connection established between the foot and the receptacle of the bedplate, relative movement can no longer occur or occurs to only a small and therefore negligible extent, so that the apparatus is substantially more reliable by comparison with conventional apparatus.

It should be noted that the receptacle, which is shaped to be complementary to the foot, for twist-resistant reception of the foot can also be provided in appropriately designed components other than a rail bedplate if this is expedient for implementing the inventive concept.

The foot can be of diverse configurations in order to realise a mechanically positive connection with the receptacle in the bedplate.

Such a connection between the axle element, in particular the foot thereof, and the bedplate, in particular the receptacle thereof, can be produced by constructionally simple means if, for example, the foot is recessed in or passes completely through the bedplate.

It is therefore advantageous if, relative to the longitudinal axis of an elongate base body of the axle element, the foot protrudes in radial direction laterally beyond the base body.

In that case, the radial direction extends transversely to the axis of rotation.

As a result, the foot can at the same time form an abutment on the axle element so that the element can be fixed perpendicularly to the bedplate, i.e. in the direction of the axis of rotation.

The mechanically positive connection between the axle element and the bedplate can be achieved in constructionally simple manner by the foot having an asymmetrical configuration.

Such asymmetry of the foot additionally provides unique mounting of the foot with respect to the bedplate so that a vertical axis of rotation is simple to achieve even by untrained persons.

In a preferred embodiment the foot is disc-shaped with a varying diameter. As a result, asymmetry of the foot can be easily achieved, wherein the disc-shaped foot can be of, in particular, flat construction so that it can be mechanically positively embedded in the bedplate.

The foot can have the form of, for example, a disc with an arcuately curved edge which goes over into a straight edge. As a result, unique positioning and resistance to twisting of the axle element with respect to the bedplate can be ensured.

The bellcrank or angle lever of the apparatus can be advantageously mounted on the axle element if the apparatus includes a bearing sleeve for mounting a hub of the lever, the sleeve being placed on the axle element so as to be arranged at least partly between the element and the hub.

By virtue of the sleeve, direct frictional contact between the lever and the axle element is avoided so that the connection between the element and the bedplate is loaded to a lesser extent by relevant forces and/or moments.

It is also advantageous if the sleeve has a bore with an internal thread by means of which the sleeve can be screwed onto the axle element in such a way that the foot can be braced or urged against the bedplate. By this means, a particularly secure retention of the foot in the receptacle of the bedplate can be ensured.

This means that by screwing the sleeve onto the axle element the foot is drawn, in the axial direction of the element, more strongly into the receptacle of the bedplate and therefore into the bedplate itself the further the sleeve is screwed onto the element.

It is also advantageous if the sleeve has a pin with an external thread, which pin is arranged at an end of the sleeve remote from the internal thread and protrudes axially beyond the hub of the lever. Consequently, the sleeve can receive the axle element internally and also externally carry, for example, a retaining nut for securing the lever on the element.

In this respect, in a further preferred embodiment the apparatus includes first loss prevention means with a retaining nut which is screwed onto an external thread of the sleeve so that the lever is secured with respect to the axle element against unintentional axial displacement. By virtue of loss prevention means of such a kind, the construction of the apparatus can be further simplified and the apparatus can be designed to be even more reliable in operation.

It is also advantageous if the apparatus includes further loss prevention means inserted through the sleeve and screwed into an internal thread of the axle element so that the sleeve is secured with respect to the element against unintentional axial displacement.

Such a sleeve can thus perform multiple functions, namely mounting of the lever on the axle element and reception of a retaining nut for realising the first loss prevention means. Independently thereof, the sleeve also serves as a stressing element to brace the axle element with respect to the bedplate.

The further loss prevention means can be particularly simple in nature if it comprises a setscrew screwed axially into the axle element. In this respect it is advantageous if the axle element has a threaded bore accessible from the end of the element remote from the foot. This threaded bore is preferably disposed centrally in the axle element.

The threaded bore is preferably a blind bore so that the axle element can be solid in the region of its foot, with the result that the element is particularly stiff in this region.

The axle element, in particular its elongate base body, can be of integral construction, but preferably the element is of two-part construction, in particular a socket part which has the foot and a screw part which can be screwed into this socket part.

As a result of this division, the sleeve can be screwed into the socket part after it has been pushed through the bedplate and the sleeve can be additionally supported -by a thicker wall region - on the screw part screwed into the socket part. The sleeve can additionally be braced by means of this screw part against the socket part so that the apparatus overall is very compact and provides an operationally reliable mounting of the lever.

The apparatus can be even stiffer with respect to the axle element if the apparatus comprises a bearing eye element which extends in the longitudinal direction of the axle element, wherein the bearing sleeve for mounting the hub of the lever is inserted from the upper side of the bearing eye element and the axle element, at least in part, is inserted from the lower side of the bearing eye element.

The bearing eye element can be of particularly simple construction if it has a collar in which the sleeve is seated and a platform from which this collar extends upwardly along the axis of rotation.

The platform preferably has elevations with passages through which screws can be inserted to screw and thus fasten the bearing eye element to the bedplate. The elevations are formed on an underside of the platform, i.e. on the side of the platform remote from the collar.

If the changeover assisting apparatus is mounted correctly the elevations are inserted into corresponding depressions in the bed plate so that a mechanically positive connection is provided between the bearing eye element and the bed plate. As a result, a particularly stable connection between the bearing eye element and the bedplate is provided.

In an embodiment of the arrangement, the changeover switching apparatus is of a switching device for switching a set of railway points and the rail bedplate is for carrying a rail. The apparatus comprises an angular lever portion for actuating the points operating linkages of adjusting devices of the set of railway points. The axle element is a vertical axle element for mounting the angular lever portion. The vertical axle element is passed through a through hole provided in the rail bedplate. The foot part of the vertical axle element is fixed positively in the receptacle of the rail bedplate whereby the footplate is pressed into the receptacle by means of a bearing sleeve screwed onto the vertical axle element. The angular lever portion is mounted on the bearing sleeve rotatably with respect to the vertical axle element. The angular lever portion is secured against any unintentional axial displacement by means of a retaining nut screwed onto the bearing sleeve.

In such an arrangement, the changeover assisting apparatus and the bedplate are operatively connected with one another in a particularly compact manner so that the afore-described disadvantages of conventional changeover assisting apparatus can be eliminated in a constructionally simple manner. A preferred variant of the arrangement provides that the bearing sleeve is braced with respect to the axle element and the retaining nut is braced with respect to the sleeve by means of a setscrew element screwed into the axle element in axial direction.

It is particularly advantageous if the receptacle for mechanically positive fixing of the foot is formed by a recess in the material of the bedplate.

Advantageously, this recess is formed at the underside, i.e. at the side remote from the apparatus, of the bedplate so that from the underside the foot of the axle element can be mechanically positively urged against the bedplate by a simple constructional measure. Consequently, the connection between the axle element and the bedplate is formed directly. Since the recess is formed directly on the bedplate, the connection can be of particularly flat format.

The mounting of the axle element on the bedplate and the structure of the apparatus in general can be further simplified if the receptacle includes the passage by which the axle element can be pushed through the bedplate. This means that the receptacle and the passage are formed to coincide in the bedplate.

Advantageously, the foot can be releasably braced against the bedplate by means of the sleeve. To that extent, the sleeve at the same time forms a clamping element at the apparatus and therefore serves not just for mounting the hub of the lever.

Advantageously, the elongate base body of the axle element also forms the foot, with the result that the apparatus has an even simpler construction.

As a consequence of the design of the changeover assisting apparatus and the arrangement comprising this apparatus and a rail bedplate, the previously required intermediate plate can be dispensed with, since the vertical axle element of the apparatus can be fastened directly to the bedplate, specifically fixed in a twist-resistant manner by a mechanically positive or shape-locking/interlocking connection.

In this regard, it is advantageous if the axle element starting from the bedplate is pushed through the provided passage, i.e. inserted through the bedplate, in which case the foot of the axle element is mechanically positively fixed in the receptacle of the bedplate and the foot is preferably drawn into this receptacle by means of the bearing sleeve screwed onto the axle element, the bellcrank lever being mounted on the sleeve to be pivotable with respect to the axle element.

Preferably, the bedplate has a rail mounting region, which has a rail mounting position, and an apparatus mounting region, the changeover assisting apparatus being mounted on the apparatus mounting region at a spacing from the rail mounting position. For preference, the rail mounting region and the apparatus mounting region are formed by respective regions of a plate body of the bedplate. A preferred embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which components which at least substantially correspond with respect to their function are denoted by the same reference numerals and in which:

Fig. 1 shows a perspective view of an arrangement embodying the invention, comprising changeover assisting apparatus mounted on a rail bedplate;

Fig. 2 is a schematic exploded view of the apparatus of Fig. 1; and

Fig. 3 is a schematic sectional view, to an enlarged scale, of part of the arrangement in Fig. 1.

Referring now to the drawings, there is shown an arrangement comprising changeover assisting apparatus 1, which is in the form of a compact unit 2, and a rail bedplate 3 mechanically positively connected with the apparatus.

The bedplate 3 is divided into two mounting regions 5 and 6, namely a rail mounting region 5 and an apparatus mounting region 6, wherein disposed between these two regions 5 and 6 is a rail fastening element 7 to which a rail (not shown) can be firmly screw-connected.

Whereas the rail mounting region 5 and fastening element 7 are known from the prior art, the bedplate 3 differs by provision of the apparatus mounting region 6, which in the past was not provided directly at such a rail bedplate. On the contrary, the changeover assisting apparatus was in the past positioned adjacent to the rail bedplate, in which case the apparatus and the bedplate were connected by means of a separate, steel intermediate plate.

The changeover assisting apparatus 1 comprises an angle lever, in particular bellcrank lever 10, having a first lever arm 11 and a second lever arm 12 which extend at right angles to one another from a hub 13 of the lever 10.

As known from the prior art, points operating linkages (not shown) of setting or adjusting devices (also not shown) of at least one set of railway points (not shown) can be fastened to these arms 11 and 12.

In addition, the apparatus 1 comprises a vertical axle element 16 which defines a vertical axis 16 of rotation at the apparatus 1 or the bedplate 3 and which is arranged substantially perpendicularly to the upper side 17 of the bedplate 3. The references in this specification to vertical and substantially vertical refer to use of the apparatus and, in particular, use of the bedplate, namely when the bedplate is placed on the ground or other supporting substrate and the apparatus, particularly the bellcrank lever, is at the top of the bedplate. The ground or other supporting substrate is assumed to be horizontal or substantially horizontal, but obviously may be sloping, in which case vertical and substantially vertical are then to be understood as signifying substantially perpendicular to the plane of the surface on which the bedplate is placed.

The axle element 15 extends with its length dimension 18 in axial direction 19 along the vertical axis 16 of rotation. The lever 10 is mounted to be rotatable, specifically pivotable, about the axis 16 by means of the axle element 15.

In order to secure the changeover assisting apparatus 1, in particular the axle element 15 thereof, directly to the rail bedplate 3 to be securely resistant to twisting in operation, the axle element 15 has a foot 20 by means of which the element 15 is mechanically positively engaged in a receptacle 21, which is formed to be complementary thereto, of the bedplate 3. The foot 20 here projects in radial direction laterally beyond an elongate base body 23 of the axle element 15. The base body 23 is composed, at least in this embodiment, of two components 24 and 25, namely a socket part or socket 24 extending from the foot part or foot 20 and a screw part or screw 25 which can be screwed into this socket part 24, the screw part in this case being a setscrew element 26.

The laterally projecting foot part 20 forms an abutment so that the axle element 15 when pushed from the underside of the bedplate 3 through a passage 28 communicating with the receptacle 21 can be fixed, in particular mechanically positively fixed, in axial direction to the bedplate 3, as described in detail further below.

The vertical axle element 15 is positioned and aligned uniquely in the receptacle 21 of the bedplate 3, since the foot part 20 is of asymmetrical form. In that regard, the foot part 20 is approximately disc-shaped so that it has a relatively flat form in the length dimension 18 of the axle element 15 of the base body 23 so that it can be accommodated in its entirely in the bedplate 3.

The asymmetry of the foot part 20 is achieved by a varying diameter, which is achieved by the edge 29 of the foot part 20 having a curved region 29A and a straight region 29B.

The foot part 20 thus has a flattened circumferential edge region which enables the foot part 20 to be inserted in mechanically positive manner into the receptacle 21, which is of complementary shape, in the bedplate 3. By this means, a constructionally simple mechanically positive connection arises between the axle element 15 of the apparatus and the bedplate 3.

In order to permanently and reliably secure the connection between the apparatus 1 and the bedplate 3, the apparatus also comprises a clamping element in the form of a bearing sleeve 30 for mounting the hub 13 of the lever 10 on the axle element 15.

The sleeve 30 has a bore 31 with an internal thread which is complementary to an external thread of the socket part 24 of the axle element 15 so that the sleeve 30 can be screwed onto the socket part 24.

If the sleeve 30 is screwed to a sufficient extent onto the socket part 24 in the axial direction 19, the foot part 20 of the axle element 15 is drawn in the axial direction 19 into the receptacle 21 in the bedplate 3 until the sleeve 30 bears against the bedplate 3 so that the sleeve 30 is urged against the upper side 17 and the foot part 20 against the lower side 27 of the bedplate 3.

The apparatus 1 is thus mechanically positively fixed in twist-resistant manner directly to the bedplate 3 by this means alone.

In that case, the sleeve 30 is disposed at least partly between the axle element 15 and the hub 13 of the lever 10, wherein the hub 13 and the sleeve 30 enable a corresponding sliding mounting of the lever 10 in the apparatus 1.

As a result, during movement of the lever 10 about the vertical axis 16 of rotation a smaller force or moment acts on the actual axle element 15 so that advantageously the connection between the foot part 20 of the axle element 15 and the bedplate 3 is less strongly loaded.

In order for the sleeve 30 to interact on the one hand with the socket part 24 of the axle element 15 and on the other hand with the thinner screw part 25 of the axle element 15 the sleeve 30 has a variable cross section in the length dimension 18 of the axle element 15. In particular, the cross-section defines a thicker annular region 33 in the upper region of the hub 13. A pin 35 with an external thread is formed on the end region 34 of the sleeve 30 remote from the bore 31, which pin protrudes axially beyond the hub 13 of the lever 10 when the apparatus 1 is correctly mounted. A retaining nut 38 is screwed onto the external thread of the pin 35 so as to prevent the lever 10 from being unintentionally displaced with respect to the axle element 15 in the axial direction 19 and possibly detaching from the axle element 15.

The retaining nut 38 is secured against unintentional release by the setscrew element 26, which is inserted from above through the sleeve 30 and screwed into the threaded bore 39 of the socket part 24.

The bore 39 is accordingly accessible from an end 40 of the axle element 15 remote from the part 20.

The retaining nut 38 and the setscrew element 26 are respectively tightened against washers 41 and 42.

The retaining nut 38 screwed onto the external thread of the sleeve 30 so that the lever 10 is secured against unintentional axial displacement with respect to the axle element 15 constitutes a first loss prevention device 43 in the apparatus 1.

In addition, the setscrew element 26 inserted through the sleeve 30 and screwed into the socket part 24 constitutes a further loss prevention device 44 of the apparatus 1.

The apparatus 1 in this embodiment additionally has a bearing eye element 45 extending in the length direction 18 of the axle element 15. Both the socket part 24 of the axle element 15 and the bearing sleeve 30 are pushed through the bearing eye element 45 so that the sleeve 30 has more stable guidance in the bedplate 3.

The sleeve 30 is inserted from the upper side and the socket element from the lower side of the element 45.

The bearing eye element 45 has a mounting platform 48 which is mounted over a large area on the bedplate 3 by means of four screw connections (not shown).

In that respect, a respective mounting shank or spigot 49 (only one is numbered in Fig. 3) is formed on the platform 48 at each of the four screw connections so as to enable a mechanically positive connection between the bearing eye element 45 and the bedplate 3.

The changeover assisting apparatus 1 constructed in such a manner and mounted directly on the rail bedplate 3 on the one hand has a very compact structure and on the other hand avoids the disadvantages known from the prior art, so that adjusting devices for sets of railway points can be more reliable in construction and design.

By means of the changeover assisting apparatus 1 and the rail bedplate 3 there is produced the arrangement 4 in which the axle element 15 is pushed through the passage 28 in the bedplate 3 starting from the underside 27 thereof and in which the foot part 20 of the axle element 15 is fixed in mechanically positive or shape-locking/interlocking manner in the receptacle 21 of the bedplate 3, the foot part 20 being drawn into this receptacle 21 by means of the bearing sleeve 30 screwed, in particular tightened, onto the socket part 24 of the axle element 15.

The bellcrank lever 10 of the apparatus 1 is mounted on the sleeve 30 to be rotatable with respect to the axle element 15, the element 15 being secured - by means of the retaining nut screwed onto the sleeve 30 - against axial displacement. In addition, the sleeve 30 is braced against the axle element 15 and the retaining nut 38 against the sleeve 30 by means of the setscrew element 26 screwed in the axial direction 19 into the socket part 16 of the axle element 15. This arrangement provides a particularly reliable coupling point for a switching device for switching one or more sets of railway points.

It will be understood that the afore-described embodiment represents merely one embodiment of the changeover assisting apparatus and associated arrangement according to the invention and the invention is not restricted to this embodiment.

Claims

PATENT CLAIMS

1. Arrangement comprising a rail bedplate and changeover assisting apparatus, the apparatus being mounted on the bedplate, wherein the changeover assisting apparatus comprises a beilcrank lever to which points operating linkages of adjusting devices of a set of railway points are coupleable and an axle element on which the lever is mounted to be pivotable about an axis of rotation, wherein the axle element has a foot formed so that the axle element is fitted by means of the foot in a receptacle of substantially complementary form in the rail bedplate to be secure against rotation relative to the bedplate and to extend substantially vertically in use of the bedplate so that the axis of rotation is substantially vertical.

2. Arrangement according to claim 1, wherein the axle element comprises an elongate body and the foot protrudes laterally of the body substantially radially with respect to the length direction thereof.

3. Arrangement according to claim 1 or claim 2, wherein the foot is of asymmetrical form.

4. Arrangement according to any one of the preceding claims, wherein the foot is disc-shaped with a diameter that varies with radial angle.

5. Arrangement according to any one of the preceding claims, comprising a bearing sleeve mounting a hub of the lever, the sleeve being mounted on the axle element so as to be arranged at least partly between the axle element and the hub.

6. Arrangement according to claim 5, wherein the sleeve has a bore with an internal thread by means of which the sleeve can be screwed onto the axle element to draw the foot of the axle element into the receptacle of such a bedplate and brace the foot against the bedplate.

7. Arrangement according to claim 5 or claim 6, wherein the sleeve has at an end thereof remote from the internal thread an externally threaded pin protruding axially from the hub of the lever.

8. Arrangement according to any one of claims 5 to 7, comprising lever loss prevention means which comprises a retaining nut screwed onto an external thread of the sleeve so that the lever is secured with respect to the axle element against axial displacement. «

9. Arrangement according to any one of claims 5 to 8, comprising sleeve loss prevention means which is inserted through the sleeve and screwed into an internal thread of a part of the axle element so that the sleeve is secured with respect to the axle element against axial displacement.

10. Arrangement according to claim 9, wherein the sleeve loss prevention means comprises a setscrew.

11. Arrangement according to any one of the preceding claims, wherein the axle element has a threaded bore accessible from an end of the element remote from the foot.

12. Arrangement according to any one of the preceding claims, wherein the axle element comprises a socket having the foot and a screw which can be screwed into the socket.

13. Arrangement according to any one of claims 5 to 10, comprising a bearing eye element extending in the axial direction of the axle element, the sleeve being inserted into the bearing eye element from an upper side thereof and the axle element being inserted into the bearing eye element from a lower side thereof.

14. Arrangement according to any one of claims 5 to 10, wherein the axle element extends through a passage in the bedplate so that the foot of the axle element is received in the receptacle, the receptacle being at a lower side of the bedplate, remote from the apparatus and the foot being urged into the receptacle by means of the bearing sleeve screwed onto the axle element, wherein the hub of the lever is mounted on the sleeve to be rotatable relative to the axle element and the lever is secured against axial displacement by means of a retaining nut screwed onto the sleeve.

15. Arrangement according to claim 14, wherein the sleeve is braced relative to the axle element and the retaining nut relative to the sleeve by means of a setscrew screwed into part of the axle element.

16. Arrangement according to any one of the preceding claims, wherein the bedplate has a rail mounting region, which defines a rail mounting position, and an apparatus mounting region, the changeover assisting apparatus being mounted on the apparatus mounting region at a spacing from the rail mounting position.

17. Arrangement according to claim 16, wherein the rail mounting region and the apparatus mounting region are formed by respective regions of a plate body of the bedplate.