CN111497888A

CN111497888A - Automatic traction coupling

Info

Publication number: CN111497888A
Application number: CN202010052419.7A
Authority: CN
Inventors: M.舒勒; A.施文林
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2019-01-31
Filing date: 2020-01-17
Publication date: 2020-08-07
Also published as: CN212047360U; EP3689705B1; DE102019102455A1; EP3689705A1; PL3689705T3

Abstract

An automatic traction coupling with a coupling head, which comprises a coupling head housing and an interlocking device with a stop means, which is designed as a rotary locking mechanism with an attachment lug and a central part, wherein the central part can be rotated about a main axis between a ready-for-attachment position, an attachment position and a release position, the attachment lug being attached to the central part with a first end and having a free second end; the central member having an opening for receiving a second end of an attachment lug of an opposing connector; the limiting device comprises a punch and a lock rod; the punch in a first position locks the lock bar in a detent position and in a second position releases the lock bar from the detent position. The automatic traction coupling is characterized in that the arresting position of the locking lever is positioned such that the locking lever is moved into the arresting position before the centre piece reaches the disengagement position of the centre piece.

Description

Automatic traction coupling

Technical Field

The invention relates to an automatic traction coupling, in particular for a freight car of a rail vehicle, according to the preamble of claim 1.

Background

Automatic traction couplings of this type are known from practice, which have a coupling head with a coupling head housing and an interlocking device with a stop device. The locking device is designed as a rotary locking mechanism with an attachment lug and a central part, wherein the central part is rotatable about a main axis between a ready-for-attachment position, an attachment position and a release position, and the attachment lug is rotatably attached to the central part about an attachment lug axis by means of a first end and has a free second end. The central member has openings for receiving the respective second ends of the attachment lugs of the opposing connectors.

The central part is provided with a spring energy storage. The center part can be pivoted out of the connection position into the disconnection position against the force of the spring energy store and can be pivoted out of the disconnection position into the ready-for-connection position and out of the ready-for-connection position into the connection position by the force of the spring energy store.

The locking device, which secures or releases the locking device in each case in a suitable position in order to be switched over to the other position by rotation of the center part, has a punch which is movable in the connecting direction of the traction coupling against a spring force and a locking lever which is movable transversely or obliquely with respect to the connecting direction. The locking lever is articulated on the central part and is moved by the central part into a locking position when the central part is rotated from the connection position into the disconnection position, in which locking lever the central part is prevented from rotating in the opposite direction, i.e. in the direction from the disconnection position into the connection position. The punch is also movable between a first position and a second position. In the first position, the plunger has moved against the spring force, in the first position the plunger blocks or locks the locking lever in the retaining position, in the second position the plunger has been moved out of the first position by the spring force, in the second position the plunger releases the locking lever from the retaining position.

The principle of action of this kind of self-traction coupling is as follows: two opposite connecting heads on two vehicles to be connected to one another are braked against one another in such a way that the second end of the respective connecting lug is inserted into the opening of the center piece of the respective other connecting head and is held in a positive-locking manner by the rotation of the center piece there. Thereby mechanically interconnecting the two vehicles. The two interlocking devices are loaded solely by the tensile force which is distributed evenly to the two attachment lugs within the parallelogram formed by the attachment lugs and the central piece. Instead, the pressure is transmitted via a special contour on the front side of the connector housing, wherein this contour usually (preferably also in the present invention) comprises a cone and a funnel, which are surrounded by a wide, in particular flat, end face. The profile may be formed by a separate end plate which is fixed to the front part of the connector housing. The profile can form a sliding surface and a centering surface with the cone and the funnel body and determine the clamping area in particular in the form of a lateral offset, a height offset and an angular offset. When the two connectors collide, the two connectors are mutually centered and slide in an embedded mode.

When two rail vehicles are moved toward one another, their locking devices or their centers are in the ready-for-connection position, in which they are held by the locking lever in the locking position. When in connection, the cone bodies respectively extend into the funnel bodies connected with the contour of the connector shell. The cone presses the plunger and moves it back, so that the plunger releases the locking lever from its locking position. The locking device is released in this way and is rotated by the force of the corresponding spring energy store until the center part comes to a stop at a predetermined stop, usually at the connector housing. Here, the connection lugs guided in the funnel body are locked in the central part opening, the two interlocking means are hooked into one another, and the connection position is achieved. Accidental separation of the interlocking devices is not possible. Normal wear does not impair the safety of the interlocking device.

To disengage the coupling head, the disengaging device rotates the two interlocking means, i.e. the two central parts, against the force of the spring energy store until the coupling lugs are guided out of the openings in the central parts. The rotating center part moves the locking lever until, upon disconnection of the vehicle, a reverse rotation of the center part from the disengaged position beyond the connection-ready position is prevented, in that the locking lever is brought into its locking position.

Written prior art references GB 419590 a and US 2013/0146558A 1. such tip connectors are also disclosed in wikipedia, scharfenberg kupplung.ur L:https://de.wikipedia.org/w/ index.php？title＝scharfenbergkupplung&olded＝184854267and 2019, version 01, month 18.

Since the two coupling heads always interact with each other during the connection and disconnection, the traction coupling is designed such that the coupling heads or the interlocking device are actuated with respect to each other. For example, when the interlocking device is released by means of a manual release device or even by means of an automated release device, in such a way that the center piece of the interlocking device is rotated against the force of the spring energy store, the rotation is transmitted to the opposite center piece via the articulated attachment lugs on the center piece and the openings of the opposite center piece. Accordingly, the opposite hub transmits its rotation to its locking lever, bringing the locking lever into its locking position. A problem in the known traction couplings, especially for trucks, primarily for lighter vehicles, is that the inevitable play in the traction coupling or in the coupling joint (for connecting the traction coupling to the rail vehicle) causes the coupling heads to perform a decoupling movement when a rotation is transmitted from the actively actuated coupling head to the passively actuated coupling head, while a rotation of the hub of the coupling head for opening the interlock is still being performed. This results in the known traction coupling: in an advantageous manner, the connecting heads can be separated from one another, but at least the passively actuated interlocking device is not braked by its locking lever in the ready-for-connection position of its central part, but the central part is returned into the connected position again. Thereby hindering subsequent connections. Furthermore, if the opening of an air line, for example a brake air line, is also coupled to the movement of the interlock device, the brake air line can open undesirably.

Disclosure of Invention

The object of the invention is therefore to improve such an automatic traction coupling such that the locking of the center part can be reliably achieved by bringing the locking lever into the locking position even in such a passively actuated coupling head.

The above-mentioned object is achieved by an automatic traction coupling having the features of claim 1. Advantageous and particularly advantageous embodiments of the traction link according to the invention and rail vehicles with corresponding traction links are specified in the dependent claims.

The invention relates to an automatic traction coupling, in particular for a freight car of a rail vehicle, having a coupling head which comprises a coupling head housing and an interlocking device with a braking device. The locking device is designed as a rotary locking mechanism with an attachment lug (or lug, attachment snap ring) and a central part, wherein the central part can be rotated about a main axis between a ready-for-attachment position, an attachment position and a release position. The disengagement position can in principle be combined with the ready-to-connect position or, viewed from the connect position, the disengagement position is defined on the other side of the ready-to-connect position with respect to the rotation of the central part.

The attachment lugs are connected with a first end to the central piece so as to be rotatable about an attachment lug axis and have a free second end. The free second end forms, in particular, a transverse locking pin in order to achieve the lug-like shape of the connection lug.

The center piece has an opening which is arranged for receiving the second end of the attachment lug of the opposite connecting head and can be pivoted out of the attachment position into the disengagement position against the force of the spring energy store and at least from the disengagement position into the attachment position by the force of the spring energy store, in particular from the disengagement position into the ready-for-attachment position and out of the ready-for-attachment position into the attachment position by the force of the spring energy store when the disengagement position is not merged with the ready-for-attachment position. In particular, the transverse latches of the attachment lugs are inserted into the openings.

The locking device of the interlocking device has a plunger (or plunger) which is movable in the connecting direction of the traction coupling against a spring force and a locking lever which is movable transversely or obliquely with respect to the connecting direction. The locking lever is articulated on the central part and is moved by the central part into a locking position when the central part is rotated from the connecting position into the disconnecting position, in which the locking lever prevents the central part from being rotated from the disconnecting position into the connecting position.

In the first position moved against the spring force, the punch locks the lock lever in the detent position, and when the punch is in the second position moved by the spring force, the punch releases the lock lever from the detent position.

According to the invention, the locking position of the locking lever is positioned such that it is selected such that the locking lever has been moved into the locking position before the centre piece has reached its disengagement position. In other words, the center piece does not have to be completely rotated out of the connecting position into the maximum achievable deflection position of the center piece, in which it occupies the disengagement position, in order to move the locking lever into the blocking position of the locking lever. Conversely, the locking lever has already advanced to the stop position even if the hub has not rotated as far as possible in the direction from the connected position to the disconnected position. That is, the locking lever has reached the stop position in a predetermined rotational position of the centre piece in the rotational direction from the coupling position to the decoupling position, wherein the predetermined rotational position has a rotational angle difference with respect to the rotational position of the centre piece in the maximum possible rotational position or rotational position. In contrast to the prior art, the locking lever therefore reaches the locking position earlier, which can be achieved, for example, by the locking projection of the locking lever engaging with the locking projection of the guide for the locking lever earlier when the hub has not yet been completely rotated out of the connecting position into the maximum achievable deflection position of the hub, in which the hub assumes the disengaged position. The conventional locking lever can be modified, for example, in that its stop lug is positioned relatively farther from the connection of the locking lever to the center piece and/or in that the stop lug of the guide piece is positioned relatively closer to the connection of the locking lever to the center piece.

The solution according to the invention ensures that the locking lever is locked in the counter bearing at least as soon as the plunger is moved from the second position into the first position, even if the center part connected to the locking lever has not previously been rotated to the maximum in the direction of the disengagement position. This is particularly important for starting the passively actuated interlocking device, in which the center piece is not rotated directly by an automated disengaging device connected to the center piece or by a manual disengaging device, but is rotated indirectly by the opposite center piece and the coupling lugs connected to the center piece or by the opposite center piece and its own coupling lugs, which are correspondingly displaced by the opposite center piece.

When reference is made herein to the stop position, a displacement position of the locking lever is defined in which the locking lever has been displaced far enough in the direction of the plunger to block (by the plunger being released in its second position) on the counter-bearing, for example on a guide of the plunger. This means that the locking lever can assume a stop position, which can also be referred to as a stop ready position accordingly, before the punch releases the actual blocking with the counter bearing.

It is particularly advantageous if the punch has an opening which at least partially or completely surrounds the locking lever and the locking lever forms a locking connection with the counter bearing, in particular on the guide of the punch, by means of two mutually engageable locking projections, which may also be referred to as locking lugs, wherein the locking lever can be actuated by a displacement of the punch from the first position into the second position in order to end the mutual engagement of the locking projections.

In particular, the locking lever has a latching projection which is positioned so as to be moved beyond the latching projection of the mating bearing when the hub connected to the locking lever is rotated out of the connecting position into the disengaging position, wherein in the disengaging position, i.e. in the greatest deflection of the hub in the direction from the connecting position into the disengaging position, a spacing in the direction of movement of the locking lever is formed between the latching projections. It is thereby particularly clear that the locking position of the locking lever is advantageously positioned such that the locking lever has already been moved into the locking position or into the position ready for locking before the center piece has reached the disengaged position or even the disengageable position of the center piece, so that the locking lever has already been moved beyond the locking position in the disengaged position of the center piece, as it were.

According to one embodiment of the invention, a resilient spring element is provided, against the spring force of which the locking lever can be moved into the locking position. In particular, the spring element is positioned such that the latching projections are pressed against one another transversely to the direction of displacement of the locking lever in order to engage with one another.

Preferably, the punch can engage with the locking lever in the region of the opening in such a way that, when the punch is moved from the first position into the second position, the punch moves the locking lever against the spring force of the spring element.

Preferably, the coupling head has manual disengagement means. In this case, according to one embodiment, the manual release device can be accessed for its actuation only from a side transverse to the connection direction. The manually operated release device, which is complicated in design and is arranged on both sides, can be dispensed with, and the operating time can be reduced, since it is ensured according to the invention that even a passively actuated locking device is always reliably brought into the desired connection-ready position.

If a pulse line for transmitting the release pulse is provided in the case of a pneumatic release cylinder, this pulse line for transmitting the release pulse and for supplying the release cylinder of the mating coupler can be omitted in the solution according to the invention, wherein the gap in the coupling or in the coupler knuckle, which is described above, can be eliminated by the pulse line.

Even the handling procedure at the moment of disengagement can be simplified. Braking and crushing of the vehicles of the longer train before the separation of the transport means can be eliminated.

The solution according to the invention ensures, in particular, an improved geometric arrangement of the latching lugs on the locking lever, which ensures that the passively actuated locking device brakes the two connecting heads in the ready-for-connection position in the movement superimposition consisting of the opening of the (two) locking device and the separating movement of the (two) connecting heads. The air connection valve is therefore also reliably closed when it is provided, which is controlled by an interlocking movement about the main axis. In this way, venting of the main air line is avoided and the corresponding rail vehicle is braked to the greatest possible extent in the shunting region. Hitherto, in particular for longer cabin units, the stopper device has been released by the necessary filling air reservoir, which leads to disadvantageous delays.

The manual disengagement means comprise, for example, a cable or another transmission having at least one chain, link or lever system. In particular, the disengagement movement is transmitted by means of a cable to disengagement levers which cause a rotation of the respective centers.

The central part is in particular supported on the kingpin and is advantageously connected to the kingpin in a rotationally fixed manner, so that the central part is also rotated by the rotation of the kingpin. The kingpin accordingly extends along the main axis and can be rotated about the main axis.

Correspondingly, the manual disengagement means can also act on the kingpin for its rotation.

Manual uncoupling devices are used in particular when there is no energy for automated uncoupling, for example in traction couplings on freight cars.

The disconnection, i.e. the opening of the interlocking device, can thus also take place directly at the coupling head at the end of the car.

If, as mentioned above, the rotation of the interlocking device with the manual disengaging device is transmitted to the opposite coupling head, no additional manipulation of the manual disengaging device of the opposite coupling head is required.

The rail vehicle according to the invention has an automatic traction coupling of the kind described.

In particular, the rail vehicle comprises a plurality of carriages, motor cars and/or passenger cars/trucks, which are each connected by means of an automatic traction coupling according to the invention, wherein each automatic traction coupling has two respective connecting heads, wherein the center part of one (passively actuated) locking device is influenced indirectly by a rotation of the center part of the other (actively actuated) locking device in such a way that the rotation is transmitted via the connecting lugs.

Drawings

The invention is illustrated below on the basis of an embodiment and the accompanying drawings.

Wherein:

fig. 1 shows a cross-sectional view of an automatic traction coupling according to the invention;

fig. 2 shows a schematic view of a traction coupling according to the invention with two coupling heads connected to each other;

fig. 3 shows a diagonally rear view and a diagonally front view of a coupling head of a traction coupling according to the invention;

fig. 4 shows a schematic view of two connection heads of an automatic traction coupling in a connection position;

fig. 5 shows the connecting head of fig. 4 in a disengaged position;

FIG. 6 shows a schematic view of two connecting heads when transmitting rotation from the center piece of an actively operated interlocking device to the center piece of a passively operated interlocking device;

FIG. 7 illustrates the position of the locking bar when disengaged in accordance with a prior art passively operated interlock;

fig. 8 shows the corresponding position of the locking lever in the case of a connecting head of a traction coupling according to the invention.

Detailed Description

Fig. 1 schematically shows an exemplary embodiment of an automatic traction coupling according to the invention in a coupling-ready position of the interlock device 3 or of its central part 6. Specifically, the automatic traction coupling includes a coupling head 1, and the coupling head 1 includes a coupling head housing 2 and an interlocking device 3. The interlocking device 3 is designed as a rotary locking mechanism with a central part 6, to which the attachment lugs 5 are attached so as to be rotatable about an attachment lug axis 8. The central piece 6 is in turn rotatable about the main axis 7. For this purpose, the center piece 6 is supported on the kingpin 19 and is connected to it in a rotationally fixed manner.

As fig. 1 to 3 show, on the main bolt 19, on the one hand, a manual release device 4 is acted upon for manual release of the interlock device 3, and on the other hand, an actuator 20 of a valve, not shown in detail here, of a compressed air line, in particular a brake air line H L, can be controlled via the main bolt 19, such that when the interlock device 3 is rotated into the connected position, the valve is opened and when the interlock device 3 is rotated into the released position or into the ready-for-connection position, the valve is closed.

The attachment lugs 5 have a first end 5.1, at which they are rotatably attached to the central piece 6, and an opposite second end 5.2, which can be clipped into an opening 9 of the central piece 6 of the opposite connecting head 1, so that the two connecting heads 1 are mechanically locked to one another, as shown, for example, in fig. 2 and 4. The attachment lug 5 accordingly has a transverse locking at its second end 5.2, which is not shown in detail here.

The central part 6 of each connecting head 1 can be rotated against the force of a spring store 10, which spring store 10 is formed, for example, by one or more tension springs, from a disengaged position (fig. 5) into a connecting position (fig. 4) or into a connecting-ready position (fig. 1), as shown in fig. 2 and 6.

Each coupling head 1 has a punch 11 which is movable in the coupling direction of the traction coupling, i.e. in the direction of the longitudinal axis of the coupling head 1, the punch 11 being linearly movable in a guide 15 between a first position and a second position. The punch 11 cooperates with a locking rod 12 which is articulated with one axial end to the central part 6 and which, as shown in fig. 8, passes through an opening 13 of the punch 11. In addition, the locking lever 12 has a locking lug 16 in the region of the opening 13, which locking lug 16 can engage with a locking lug 17 in order to prevent a movement of the locking lever 12 from its second end in the direction of its first end connected to the hub 6 and thus a corresponding rotation of the hub 6. In the exemplary embodiment shown, the latching projections 17 are arranged on the guide 15, the guide 15 forming the counter bearing 14 for establishing a latching connection with the locking lever 12.

A resilient spring element 18 acts on the locking lever 12 to form a snap-fit of the two latching

projections

16,17, and conversely, when the plunger 11 is moved from the first position into the second position, the plunger releases the locking lever 12 from the latching connection with the counter bearing 14 against the force of the spring element 18.

In the second position of the plunger 11, the center piece 6 is thus rotated by the force of the spring store 10, which rotation is, in turn, locked in the locking position of the locking lever 12.

Each connecting head 1 has on its free end face a contour with a cone 21 and a funnel body 22. The cone 21 and the funnel 22 are surrounded by a flat end surface 23. In the exemplary embodiment shown, the contour or end face 23 is formed by an end plate 24, which can be designed as an integral part of the connection head housing 2 or can be connected separately to the connection head housing 2.

Fig. 1 shows the ready-for-connection position of the connecting head 1 or of the interlock device 3. If in this position the two connecting heads 1 are moved toward one another, the cone 21 projects into the funnel 22 and presses from the front onto the plunger 11, so that the plunger 11 is moved from its first position into its second position and releases the locking connection of the locking lever 12 to the counter bearing 14. The second end 5.2 of the attachment lug 5 is moved into the opening 9 of the center piece 6, and the center piece 6, which is no longer locked by the locking lever 12, is rotated out of the ready-to-attach position shown in fig. 1, in which the center piece 6 in particular rests on the attachment head housing 2, due to the force of the spring energy store 10, into the attachment position shown in fig. 4. Here, the connection lugs 8 guided in the funnel 22 are latched in the center piece opening 9 and the two interlocking devices 3 are hooked into one another on the inside.

The interlocking device 3 is loaded by tensile forces only, as opposed to compressive forces transmitted through the end face 23.

To disengage the coupling head 1, an automated or manual disengaging device 4 rotates the central part 6 of the actively operated interlocking device 3 against the force of the spring store 10. The coupling lugs 5 of the actively actuated locking device 3 transmit the rotation of the central part 6 via the openings 9 to the central part 6 of the passively actuated locking device 3, so that the central part 6 of the passively actuated locking device 3 also rotates against the force of the spring energy store 10. Alternatively or additionally, the center piece 6 of the actively operated interlocking device 3 transmits a rotation to the attachment lugs 5 of the passively operated interlocking device 3, so that the center piece 6 of the passively operated interlocking device 3 is thus also rotated.

When the rotation of the hub 6 in the direction of the disengagement position shown in fig. 5 continues far enough, the coupling lug 5 slides over the opening 9 of the hub 6 and the locking lever 12 is brought into its retaining position, in which the retaining connection between the locking lever 12 and the counter-bearing 14 can be established when the punch 11 (when the coupling heads 1 are separated from one another) is moved into its first position, i.e. the two retaining

projections

16,17 are hooked to one another in a form-fitting manner.

In the prior art shown in fig. 7, the blocking position is still selected such that the locking lever 12 of the passively operated interlocking device 3 does not reach the blocking position if the center piece 6 of the passively operated interlocking device 3 is not rotated far enough into the disengaged position, so that a pivoting of the center piece 6 in the direction of the connecting position is possible if no blocking connection has been established between the locking lever 12 and the counter bearing 14 or between the two blocking

projections

16, 17. In contrast, in the solution according to the invention, the stop position of the locking lever 12 is already reached when the hub 6 has not been rotated by the maximum achievable angle in the direction of the disengagement position, as shown in fig. 8. Thus, when the center piece 6 does not perform the maximum rotation from the attaching position to the detaching position, the locking lever 12 is engaged in the fitting support 14 more reliably. For example, the latching projection 16 on the locking lever 12 is located farther from the articulated connection of the locking lever 12 on the hub 6 than in the embodiment according to fig. 7 and/or the latching projection 17 on the guide 15 is located closer to the articulated connection of the locking lever 12 on the hub 6 than in the embodiment according to fig. 7.

The locking position of the locking lever 12 is achieved more safely, and even the ready-to-connect position shown in fig. 1 is thus always reliably maintained.

Fig. 6 again shows how the center piece 6 of the actively operated interlock 3 transmits its rotation to the center piece 6 of the passively operated interlock 3 via the attachment lugs 5 of the passively operated interlock 3. It is also shown that the rotation of the two centers 6 need not be completely synchronized in this way, but that the center 6 of the passively actuated locking device 3 slightly follows the rotation of the center 6 of the actively actuated locking device 3. Accordingly, the locking lever 12 of the actively actuated interlocking device 3 is moved with its locking lug 16 farther beyond the locking lug 17 than the locking lever 12 of the passively actuated interlocking device 3.

With the solution according to the invention, however, this comparatively small rotation of the central part 6 of the passively operated interlocking device 3 is sufficient to bring the locking lever 12 of the passively operated interlocking device 3 into its arresting position.

List of reference numerals:

1 connecting head

2 connector shell

3 interlocking device

4 Manual disengaging gear

5 attachment lug

5.1 first end portion

5.2 second end

6 center piece

7 main axis

8 axis of connecting lug

9 opening

10 spring energy accumulator

11 punch

12 locking bar

13 open pores

14 cooperating bearing means

15 guide member

16 stop lug

17 stop lug

18 elastic spring element

19 kingpin

20 actuator

21 taper

22 funnel body

23 end face

24 end plate

Claims

1. An automatic traction coupling, in particular for a freight car of a rail vehicle,

1.1 it has a connector (1) comprising a connector housing (2) and an interlocking device (3) with a stop device,

1.2 the interlocking device (3) is designed as a rotary locking mechanism with an attachment lug (5) and a central part (6), wherein the central part (6) can be rotated about a main axis (7) between an attachment-ready position, an attachment position and a release position, and the attachment lug (5) is attached to the central part (6) with a first end portion so as to be rotatable about an attachment lug axis (8), and the attachment lug (5) has a free second end portion (5.2);

1.3 the central piece (6) has an opening (9) for receiving a second end (5.2) of an attachment lug (5) of an opposite attachment head (1), and the central piece (6) can be rotated out of an attachment position into a disengagement position against the force of a spring energy store (10) and can be rotated out of the disengagement position into the attachment position by the force of the spring energy store (10), wherein,

1.4 the movement-limiting device comprises a plunger (11) which can be moved in the connecting direction of the traction coupling against the force of a spring and a locking lever (12) which can be moved transversely or obliquely with respect to the connecting direction,

1.5 the locking lever (12) is articulated on the hub (6) and is moved by the hub (6) into a blocking position when the hub is rotated from the connecting position into the disconnecting position, in which blocking position the locking lever (12) prevents a rotation of the hub (6) from the disconnecting position into the connecting position; wherein,

1.6 the punch (11) locks the locking lever (12) in a stop position in a first position moved against a spring force and releases the locking lever (12) from the stop position in a second position moved by the spring force;

it is characterized in that the preparation method is characterized in that,

1.7 the arresting position of the locking lever (12) is positioned such that the locking lever (12) is moved into the arresting position before the centre piece (6) reaches the disengaged position of the centre piece (6).

2. The automatic traction coupling as claimed in claim 1, characterized in that the plunger (11) has an opening (13) which at least partially or completely surrounds the locking lever (12), the locking lever (12) and the counter-bearing device (14), in particular on the guide (15) of the plunger (11), forming a locking connection by means of two mutually engageable locking projections (16,17), wherein the locking lever (12) can be actuated by the plunger (11) being moved from the first position into the second position in order to block the mutual engagement of the locking projections (16, 17).

3. An automatic traction coupling according to claim 2, characterized in that the locking lever (12) has a stop lug (16), the stop lug (16) being positioned so as to be moved beyond a stop lug (17) of the cooperating bearing means when the centre piece (6) is rotated out of the connecting position into the disengaging position, wherein in the disengaging position a spacing is formed between the stop lugs (16,17) in the direction of movement of the locking lever (12).

4. Automatic traction coupling according to one of claims 1 to 3, characterized in that a resilient spring element (18) is provided, against the spring force of which the locking lever (12) can be brought into the locking position.

5. Automatic traction coupling according to one of claims 2 to 4, characterized in that the spring element (18) is positioned for pressing the stop lugs (16,17) against each other transversely to the direction of movement of the locking lever (12) for mutual engagement.

6. An automatic traction coupling according to claim 5, characterized in that the punch (11) is engageable with a locking lever (12) in the region of the opening (13) such that the punch moves the locking lever (12) against the spring force of the spring element (18) when the punch is moved from the first position into the second position.

7. Automatic traction coupling according to one of claims 1 to 6, characterized in that the coupling head (1) has manual disengagement means (4).

8. Automatic traction coupling according to claim 7, characterized in that the manual disengagement means (4) are accessible only from one side transverse to the direction of connection.

9. A rail vehicle having an automatic traction coupling according to one of claims 1 to 8.

10. A rail vehicle according to claim 9, having two respective connecting heads (1), wherein the center piece (6) of one connecting head (1) can be actively rotated into its disengaged position and the center piece (6) of the other connecting head (1) can be passively rotated into its disengaged position in such a way that the coupling lugs (5) connected to it or to the other center piece (6) transmit the rotation of the center piece (6) of the actively actuated interlocking device (3) to the center piece (6) of the passively actuated interlocking device (3).