DE102023129426B4 - Digital Automatic Coupling (DAK) with electromechanical actuator with backlash-free drive bearing for a rail vehicle and rail vehicle with such a coupling - Google Patents

Abstract

A central buffer coupling (1) of a rail vehicle, comprising a housing (1a), a hook disc (2) with a pivot axis (2a), and an actuator (6) with an actuating element (7), wherein the actuating element (7) interacts with the hook disc (2), wherein the actuator (6) is designed as an electromechanical actuator (6) with at least one electric motor (10) and a motor brake (11), wherein the electric motor (10) of the electromechanical actuator (6) is connected to a housing (15) of the electromechanical actuator (6) by means of a connecting device (100), wherein the connecting device (100) has a connecting flange (15a), wherein the connecting device (100) comprises the motor brake (11) as a spring-loaded brake (24),
wherein the connecting device (100) has a motor mount (15e),
wherein the electric motor (10) is arranged in the motor mount (15e), wherein the spring-loaded brake (24) is arranged in a motor cover (23) of the motor mount (15e),
characterized in that the connecting flange (15a) and the motor mount (15e) are formed integrally with the housing (15) of the actuator (6).

Description

The invention relates to a digital automatic coupling (DAK) with an electromechanical actuator with play-free drive bearing for a rail vehicle according to the preamble of claim 1. The invention also relates to a rail vehicle with such a coupling.

Digital Automatic Coupling (DAK) plays a significant role in advancing digitalization and automation in rail transport. The abbreviation "DAK" will be used in the following text.

There is still a lot of catching up to do, especially in the freight transport sector, as the screw couplings between freight wagons that are still common today require both personnel and a lot of time and effort.

Process automation using DAC allows a freight train to be assembled much more efficiently, flexibly, and cost-effectively, which ultimately brings benefits for both the operator and the end customer. Furthermore, the train-wide digital interfaces enable new functionalities in terms of diagnostics, maintenance, and repair (keyword: condition-based and predictive maintenance).

The principle of the so-called Scharfenberg coupling is used both for passenger trains and is preferred by the DAK for freight trains.

The Scharfenberg coupling is well-known. It is a rigid central buffer coupling. The coupling process is purely mechanical, implemented via a hook disc and spring assemblies in each coupling head. The coupling process is purely mechanical, implemented via a hook disc and spring assemblies in each coupling head. The energy required for the coupling process is provided by the speed of the wagon to be coupled during the coupling process.

However, a decoupling process requires actuators that counteract the spring force of a spring (not shown here but conceivable) by pushing the hook disc back into the release position. In passenger trains, electro-pneumatic actuators are typically used for this purpose. The situation is different for freight trains, which is why an electromechanical drive unit is used, which operates without the use of an additional operating medium (e.g., hydraulic).

Center buffer couplings are well known in passenger train traffic, according to the state of the art. Pneumatic actuators or pneumatic cylinders are used to release these couplings. The push rod or plunger or piston of the cylinder is pushed out using pneumatically supplied energy and thus pressure, thereby rotating the hook disc or the center piece of the Scharfenberg coupling in the release direction.

document DE 10 2021 111 207 A1 describes how the same principle can be applied using an electro-hydraulic actuator. The force is also generated via pressure, which is generated by a hydraulic operating medium. An electro-hydraulic drive unit uses an electric motor to generate the necessary compression of the operating medium with a hydraulic pump and thus the pressure to move the piston forward. By maintaining the applied pressure, the actuator can maintain the force on the piston in one position for an extended period of time. For example, this is achieved by continuing to operate the electric motor to maintain the built-up pressure. After the decoupling process, the piston is retracted by reducing the pressure.

document DE 10 2021 111 206 A1 In principle, it also describes an electro-hydraulic actuator which, instead of a push rod or similar, actuates and retracts an articulated lever in order to achieve the position of the hook disc for the uncoupling process.

• In 1 is a schematic plan view of an internal structure of a central buffer coupling 1 with an electromechanical actuator 6 according to the prior art.
• 2 shows a schematic sectional view of the electromechanical actuator 6 of the central buffer coupling 1 according to 1 .
• 3 shows the schematic sectional view of the electromechanical actuator 6 according to 2 with force effects.

Such a central buffer coupling 1 according to the 1 to 3 is described in detail in its structure and function in a not yet published application by the applicant as “Digital Automatic Coupling (DAK) with electromechanical actuator for a rail vehicle and rail vehicle with such a coupling”

The central buffer coupling 1 comprises a housing 1a, a hook disc 2 with a drive section 3 and an output section 4, an eyelet 5 and an actuator 6 with a pressure rod-shaped actuating element 7. The hook disc 2 is also called the heart piece.

For uncoupling, i.e. releasing the central buffer coupling 1, the actuator 6 in the form of an electromechanical actuator 6 is used.

The actuator 6 comprises a housing 15 with a connecting flange 15a projecting downwards, and a control housing 16. A spindle drive with a threaded spindle 12 is arranged in the housing 15.

The electromechanical actuator 6 functions with the help of an electric motor 10, which converts the electrical energy into mechanical energy.

The electric motor 10 is flanged to the connecting flange 15a of the housing 15 of the actuator 6. A gear 10b is arranged in this area.

When the actuator 6 is activated, a rotary motion of the rotor of the electric motor 10 occurs in the electric motor 10. This rotary motion is further transmitted via the gear 10b to the threaded spindle 12. Since the rotating threaded spindle 12 is permanently installed in the axial direction of the actuator 6, i.e., in the direction of the central axis 6a of the actuator 6, this results in a feed movement of a spindle nut 7b and thus of the actuating element 7, which is designed here as a pressure tube and can apply the corresponding force to the hook disc 2 via a pressure head 7b.

The actuating element 7 rotates the hook disc 2 of the Scharfenberg coupling about a pivot axis 2a in the release direction. A compressive force for pivoting the hook disc 2 is transmitted to a contact point 8 of the contact point between a drive section 3 of the hook disc 2 of the Scharfenberg coupling and a free end of the actuating element 7 of the actuator 6.

The electric motor 10 has a motor axis 10a and is operatively connected to the threaded spindle 12 via the gear 10b. The gear 10b can be a spur gear, for example. The motor axis 10a and the central axis 6a of the actuator 6 are arranged parallel to each other here.

After the two trains/wagons have been completely uncoupled, actuator 6 can be returned to its original position. In contrast to the current state of the art, the electromechanical actuator 6 described here is operated purely electrically, i.e., without an additional operating medium such as pneumatics and hydraulics. This has the advantage of eliminating additional maintenance, etc., and also allowing the dynamics for force build-up and release to occur more quickly and directly.

The electric motor 10 can be a direct current motor or DC motor as the main drive for uncoupling or releasing the central buffer coupling 1.

The contact point between the pressure head 7a of the actuating element 7 and the contact point 8 has a bearing 9. The bearing 9 is a roller bearing with a roller and is arranged in the drive section 3 of the hook disk 2 so as to be rotatable about a bearing axis (not designated).

At the contact point 8, the roller of the bearing 9 contacts a pressure head 7a of the actuating element 7.

The bearing 9 minimizes the transverse forces acting on the actuating element (pressure tube) 7 and is described in more detail in another application by the applicant which has not yet been published.

In this first embodiment, a motor brake 11 flanged to the electric motor 10 supports the actuator 6 in holding a position such as the release position shown, which is also called the buffer position.

The electromechanical actuator 6 has two limit switches 13 and 14 for a starting and end position of the actuating element 7. The two limit switches 13 and 14 are arranged in the control housing 16 and are actuated by the spindle nut 10.

The housing 15 is formed with the connecting flange 15a. The connecting flange 15a has a mounting surface 15b for the electric motor 10, which is attached to the connecting flange 15a. Furthermore, an additional flange section 15c is formed on the underside 15e of the housing 15. This additional flange section 15c serves for additional mounting of the electric motor 1.

In the attached state, the electric motor 10 rests with its outer surface on a bottom side 15d of the housing 15, which runs in the direction of the central axis 6a of the electromechanical actuator 6, and is at least partially in form-fitting contact with this.

Due to vibrations and shocks, the electric motor 10 must be connected accordingly robustly by providing the motor shield or a motor flange 17 with significantly larger screw connections. attached to the housing 15 or the connecting flange 15a of the housing 15 of the actuator 6.

In addition, due to the length of the drive unit (electric motor 10 with flanged-on motor brake 11), a type of intermediate flange 18 is attached to the electric motor 10 approximately in the center of the longitudinal axis/motor axis 10a of the electric motor 10. The electric motor 10 is attached with its intermediate flange 18 to the flange section 15c of the housing 15 of the actuator 6.

In 2 - 3 The electric motor 10 is shown with a gear 10b and a drive pinion 20. In the assembled state, the drive pinion 20 is part of the gear 10b, which is then arranged in or on the connecting flange 15a.

The gear 10b also has an output gear 20a, which is connected to the threaded spindle 12 and meshes with the drive pinion 20. The gear 10b is closed by a gear cover 19.

In 3 It is shown that in this actuator 6, the drive unit is attached to the outside of the actuator housing 15 by means of two flanges (connecting flange 15a and intermediate flange 18) of a connecting device 100. The intermediate flange 18 assumes a supporting function of the drive unit by absorbing the loads (shock, vibrations) occurring radially to the motor axis 10a during a coupling process as radial forces 21 and thus reducing the loads in the connecting flange 15a.

The connecting flange 15a forms the actual connection between the drive unit and the actuator housing 15, whereby the intermediate flange 18 merely has a supporting function to absorb the radial loads (radial forces 21) mentioned above.

It is considered disadvantageous that axial loads in the direction of the motor axis 10a or parallel thereto in the direction of the central axis 6a of the actuator 6 are not transmitted through the intermediate flange 18.

The high accelerations radial to the motor axis 10a occur during a coupling impact when both coupling halves collide. This results in a bending moment 22 in the one-sided screw connection at the connecting flange 15a of the drive unit to the actuator. The bending moment 22 can occur around an axis that, in this case, runs perpendicular to the motor axis 10a. High bending moments 22 can contribute to premature failure of this connection at the connecting flange 15a.

document DE 10 2021 111 207 A1 Describes an automatic train coupling with an electro-hydraulic actuator. The force is also generated via pressure, which is generated by a hydraulic operating medium. An electro-hydraulic drive unit uses an electric motor to generate the necessary compression of the operating medium by means of a hydraulic pump and thus the pressure to move the piston forward. By maintaining the applied pressure, the actuator can maintain the force on the piston in one position for an extended period of time. For example, this is achieved by continuing to operate the electric motor to maintain the built-up pressure. After the decoupling process, the piston is retracted by reducing the pressure.

document DE 10 2021 111 206 A1 In principle, it also describes an electro-hydraulic actuator which, instead of a push rod or similar, actuates and retracts an articulated lever in order to achieve the position of the hook disc for the uncoupling process.

document DE 10 2022 123 655 A1 relates to a method for controlling a digital automatic coupling of a rail vehicle, wherein the digital automatic coupling is a central buffer coupling and has a hook disk with a drive section, an actuator with an actuating element which interacts with the drive section of the hook disk, an electric motor with a motor brake, limit switches and a control device, comprising the method steps (VS1) uncoupling by first releasing the motor brake, switching on the electric motor of the actuator in a first direction of rotation and adjusting the actuating element of the actuator from an initial position to an end position, wherein the hook disk is pivoted into its uncoupling or buffer position; (VS2) maintaining the end position of the actuator in the buffer position by applying the motor brake and subsequently switching off the electric motor of the actuator; and (VS3) adjusting the actuating element of the actuator from the buffer position to the starting position by releasing the motor brake and subsequently switching on the electric motor of the actuator in a second direction of rotation opposite to the first direction of rotation when a switching signal of an external command is present or when a signal is present that a central buffer coupling to be uncoupled has moved away from the central buffer coupling as a counter-coupling. Such a digital automatic clutch with an actuator and electric motor is specified.

It is considered a disadvantage that electromechanical actuators for uncoupling a center buffer coupling are currently only mounted outside the coupling housing. This is due to the fact that the size of the electromechanical actuator is not suitable for the tight installation space of the coupling.

With regard to the further development of the center buffer coupling actuator, particularly with optimizations in series production and cost savings in components, functional groups, assembly times, and maintenance, there is a constant need for improvements. The design, connection, and integration of the actuator's electric drive represent a key aspect.

Therefore, the object of the invention is to provide an improved central buffer coupling with an improved drive bearing for an electromechanical actuator for a rail vehicle, in which the above-mentioned disadvantages are eliminated or significantly reduced.

A further task is to provide an improved rail vehicle with such a central buffer coupling.

The problem is solved by the subject matter of claim 1.

The further problem is solved by the subject matter of claim 6.

One idea of the invention is to realize the function of an intermediate flange for fastening an electric motor of a complete electromechanical actuator in a center buffer coupling of a rail vehicle by means of a spring-loaded brake.

A central buffer coupling of a rail vehicle according to the invention, comprising a housing, a hook disc with a pivot axis, and an actuator with an actuating element, wherein the actuating element interacts with the hook disc. The actuator is designed as an electromechanical actuator with at least one electric motor and a motor brake. The electric motor of the electromechanical actuator is connected to a housing of the electromechanical actuator by means of a connecting device, the connecting device having a connecting flange. The connecting device comprises the motor brake as a spring-loaded brake.

A particular advantage of this design is that, in contrast to the previous state of the art, the function of an intermediate flange as a component of the connecting device is fulfilled by the motor brake in the form of a spring-loaded brake that is already present in the actuator.

In addition, it is a particular advantage that, as in the conventional bearing arrangement, the bearing arrangement is almost free of play in the radial direction.

A further significant advantage is provided by a standardized and cost-effective solution and the absorption of loads radial to the motor axis on the electric drive unit used in the electromechanical actuator via the spring-loaded brake.

A rail vehicle according to the invention has the central buffer coupling described above.

Advantageous embodiments are described in the subclaims.

In one embodiment, the electric motor of the electromechanical actuator is attached to the connecting flange of the actuator housing with a first end face and connected to the spring-loaded brake via a motor shaft end, which is firmly mounted on the actuator housing. In this way, the spring-loaded brake not only performs braking and holding functions, but also a bearing and force introduction function. Furthermore, the spring-loaded brake absorbs loads acting radially to the motor axis via a frictional connection, thereby relieving the load on the electric motor's drive screw connections at the connecting flange of the connecting device.

The inventive design of the center buffer coupling provides that the connecting device has a motor mount, with the electric motor arranged in the motor mount. The electric motor can advantageously be easily inserted into the motor mount during assembly.

In the inventive design of the center buffer coupling, the spring-loaded brake is located in a motor cover of the motor mount. This results in an advantageously compact design and cost-effective mounting.

The design of the central buffer coupling according to the invention provides that the connecting The flange and the motor mount are formed integrally with the actuator housing. This results in a compact and robust design and a reduction in the number of components.

The high accelerations radial to the motor axis occur during a coupling impact when both coupling halves of the center buffer coupling meet. This results in a bending moment in the connecting flange of the drive unit's connecting device to the actuator housing. The compact, one-piece design, together with the spring-applied brake, also offers the advantage of a simple and standardized device for reducing this bending moment, preventing premature failure of this connection.

The motor brake/spring-loaded brake is applied during uncoupling to ensure the buffer position. However, the motor brake/spring-loaded brake is also engaged in the deactivated/initial state, since no current flows and the motor brake is "normally closed," i.e., closed when de-energized. Therefore, coupling shocks can also occur during this process.

In one embodiment, the spring-loaded brake comprises a magnet housing, a coil, compression springs, an armature, a drive sleeve, a flange, and a friction disc. The armature is connected to the motor cover and thus to the actuator housing via the compression springs and the magnet housing. The spring-loaded brake is non-rotatably mounted on the motor shaft end of the second end face of the electric motor via the drive sleeve. This enables advantageously compact mounting and power transmission.

It is also advantageous if the driving sleeve of the spring-loaded brake engages positively and/or non-positively with a corresponding counterpart of the flange of the spring-loaded brake, as this allows a simple construction in a confined space for robust power transmission.

The frictional engagement created in the spring-loaded brake serves as a primary function to generate a holding torque that holds the actuator in the uncoupling position. Another advantageous secondary function is the frictional engagement between the friction disc and the armature, which absorbs the loads radial to the motor axis and transfers them via the spring-loaded brake's drive sleeve to the corresponding counterpart of the spring-loaded brake's flange.

In yet another embodiment, a motor axis of the electric motor runs parallel to a center axis of the electromechanical actuator, resulting in an advantageous arrangement, particularly for simple gear designs, between the electric motor and, for example, a threaded spindle for the actuating element.

• - Standardisierung durch Verwendung von Standardkomponenten.
• - Kosteneinsparung durch Einsparung des Zwischenflansches.
• - Robustere Bauweise gegenüber Vibrationen und Schocks.

The invention enables the following advantages:

• - Standardization through the use of standard components.
• - Cost savings by eliminating the intermediate flange.
• - More robust construction against vibrations and shocks.

• 1 eine schematische Draufsicht eines inneren Aufbaus einer Mittelpufferkupplung mit einem elektromechanischen Aktuator nach dem Stand der Technik;
• 2 eine schematische Schnittansicht eines elektromechanischen Aktuators der Mittelpufferkupplung nach 1;
• 3 die schematische Schnittansicht des elektromechanischen Aktuators nach 2 mit Krafteinwirkungen;
• 4 eine schematische Schnittansicht eines Ausführungsbeispiels des erfindungsgemäßen Aktuators der erfindungsgemäßen Mittelpufferkupplung;
• 5 eine schematische Schnittansicht einer beispielhaften Federdruckbremse des Ausführungsbeispiels nach 4;
• 6 die schematische Seitenansicht des Ausführungsbeispiels nach 4 mit Krafteinwirkungen; und
• 7 die schematische Schnittansicht der Federdruckbremse nach 5 mit Krafteinwirkungen.

Embodiments of the invention are described below with reference to the accompanying drawings. The invention is not limited to these embodiments. In particular, individual features of the following embodiments can be used not only in this but also in other embodiments. They show:

• 1 a schematic plan view of an internal structure of a center buffer coupling with an electromechanical actuator according to the prior art;
• 2 a schematic sectional view of an electromechanical actuator of the central buffer coupling according to 1 ;
• 3 the schematic sectional view of the electromechanical actuator according to 2 with force effects;
• 4 a schematic sectional view of an embodiment of the actuator according to the invention of the central buffer coupling according to the invention;
• 5 a schematic sectional view of an exemplary spring-pressure brake of the embodiment according to 4 ;
• 6 the schematic side view of the embodiment according to 4 with force effects; and
• 7 the schematic sectional view of the spring-loaded brake according to 5 with force effects.

1 - 3 relate to the state of the art and are explained above.

4 shows a schematic sectional view of an embodiment of the actuator 6 according to the invention of the central buffer coupling 1 according to the invention.

The actuator 6 according to the invention comprises an exemplary integration of a standardized drive unit. The drive unit has a motor 10 with a spring-loaded brake 24, both of which are arranged inserted into an interior space of a motor mount 15e. The motor mount 15e and the connecting flange 15a are formed integrally with the housing 15 of the actuator 6.

A connecting device 100 comprises the connecting flange 15a, the motor mount 15e with a motor cover 23 and the spring-loaded brake 24.

The motor 10 is secured to the connecting flange 15a of the actuator housing 15 by means of a first end face 10e via a motor flange 17 by means of screw connections. A motor shaft end 10c protrudes from the first end face 10e of the motor 10 and is connected to the drive pinion 20 of the gear 10b.

From another, second end face 10f of the motor 10, another motor shaft end 10d protrudes, which is connected to the spring-loaded brake 24. The spring-loaded brake 24 is installed in the motor cover 23. The motor cover 23 is attached here with fastening elements (screws, e.g., according to DIN 7984) to the open end of the motor mount 15e of the actuator housing 15 of the actuator 6 and closes the interior of the motor mount 15e.

The spring-loaded brake 24 is non-rotatably mounted on the motor shaft end 10d by means of a press fit or a key and is firmly mounted on the actuator housing 15 of the actuator 6 by means of a friction-locking screw connection, centered by dowel pins.

An intermediate flange 18 is completely omitted here. Its function is taken over by the spring-loaded brake 24, as explained further below.

In 5 is a schematic sectional view of an exemplary spring pressure brake 24 of the embodiment according to 4 shown.

6 shows the schematic side view of the embodiment according to 4 with force effects. 7 shows the schematic sectional view of the spring-loaded brake 24 5 with force effects.

The spring-loaded brake 24 comprises a magnet housing 24a, a coil 25, compression springs 26, an armature 27, a drive sleeve 28, a flange 29, and a friction disc 20. The splined drive sleeve 28 is firmly seated on the motor shaft end 10d of the motor 10 and engages, via a spline 28a, with a corresponding counterpart, which is attached to the flange 29. The armature 27 is connected to the actuator housing 15 via the compression springs 26 and the magnet housing 24a.

During a coupling process, when the actuator 6 reaches its uncoupling position (see 1 ), the spring-loaded brake 24 applies its torque. This creates a frictional engagement between the friction disc 20 and the armature 27. This frictional engagement is used in this embodiment not only to transmit the torque, ie to maintain the uncoupling position, but also to absorb loads acting radially to the motor axis 10a of the motor 10 (radial forces 21, 6 ), which are generated by the coupling process.

In this way, the function of the electromechanical actuator 6 from the prior art ( 1-3 ) used intermediate flange 18 is realized cost-effectively and in a standardized manner by the spring-loaded brake 24. The intermediate flange 18 is thus replaced by the spring-loaded brake 24 (see 6 - 7 ).

The spring-loaded brake 24 is applied during uncoupling to ensure the buffer position. However, the spring-loaded brake 24 is also engaged in the de-energized/initial state, since no current flows and the spring-loaded brake 24 is "normally closed," i.e., closed when de-energized. Therefore, coupling shocks can also occur during this process.

The generation of the frictional engagement in the spring-loaded brake 24 is made possible by the compression springs 26. When the electrically conductive coil 25 in the magnet housing 24a is not energized, the compression springs 25 press the armature 27 against the friction disc 30 with a defined spring force in this so-called currentless state.

This is exactly the case when the two central buffer couplings 1 to be coupled meet, whereby the high loads mentioned above occur as radial forces 21, 21a and bending moment 22, as also in 6 and 7 is indicated schematically.

When the coil 25 is energized, thus generating a magnetic field, the armature 27 is lifted off the friction disc 30. In other words, the armature 27 is moved by the friction disc 30 in the axial direction toward the motor axis 10a toward the magnet housing 24a or is attracted by it. The frictional connection between the armature 27 and the friction disc 30 is therefore no longer present.

With this frictional engagement, a holding torque is generated as a primary function, which holds the actuator 6 in the uncoupling position.

As a further secondary function, the frictional engagement between the friction disc 30 and the armature 27 of the spring-loaded brake 24 serves to absorb the loads already mentioned, which run radially to the motor axis 10a, caused by the radial forces 21, 21a.

The above-described central buffer coupling 1 according to the invention with the electromechanical actuator 6 with the spring-loaded brake 24 can be designed, for example, as a Scharfenberg coupling or other central buffer coupling 1.

• - Standardisierung durch Verwendung von Standardkomponenten.
• - Kosteneinsparung durch Einsparung des Zwischenflansches 18.
• - Robustere Bauweise gegenüber Vibrationen und Schocks.

The central buffer coupling 1 according to the invention described above offers the following advantages:

• - Standardization through the use of standard components.
• - Cost savings by eliminating the intermediate flange 18.
• - More robust construction against vibrations and shocks.

The invention is not limited by the embodiments given above, but can be modified within the scope of the claims.

For example, it is conceivable that the motor mount can simultaneously be a conventional or modified motor housing.

List of reference symbols

1

Center buffer coupling

1a

Housing

2

Hook disc

2a

Swivel axis

3

Drive section

4

Output section

5

eyelet

6

Actuator

6a

central axis

7

Actuating element

7a

print head

7b

spindle nut

8

Contact point

9

warehouse

10

electric motor

10a

Motor axle

10b

Gearbox

10c, 10d

Motor shaft end

10e, 10f

front side

11

Engine brake

12

threaded spindle

13, 14

limit switch

15

Actuator housing

15a

connecting flange

15b

Mounting surface

15c

Flange section

15d

bottom

15e

Engine mount

16

Control housing

17

Motor flange

18

Intermediate flange

19

Gearbox cover

20

drive pinion

20a

Output gear

21, 21a

radial force

22

Bending moment

23

Engine cover

24

Spring-loaded brake

24a

Magnet housing

25

Sink

26

compression spring

27

anchor

28

Driving sleeve

28a

Spline

29

flange

30

friction disc

Claims (6)

Central buffer coupling (1) of a rail vehicle, comprising a housing (1a), a hook disc (2) with a pivot axis (2a), and an actuator (6) with an actuating element (7), wherein the actuating element (7) interacts with the hook disc (2), wherein the actuator (6) is designed as an electromechanical actuator (6) with at least one electric motor (10) and a motor brake (11), wherein the electric motor (10) of the electromechanical actuator (6) is connected to a housing (15) of the electromechanical actuator (6) by means of a connecting device (100), wherein the connecting device (100) has a connecting flange (15a), wherein the connecting device (100) comprises the motor brake (11) as a spring-loaded brake (24), wherein the connecting device (100) has a motor mount (15e), wherein the electric motor (10) is arranged in the motor mount (15e), wherein the spring-loaded brake (24) is arranged in a motor cover (23) of the motor mount (15e), characterized in that the connecting flange (15a) and the motor mount (15e) are formed integrally with the housing (15) of the actuator (6). Central buffer coupling (1) to Claim 1 , characterized in that the electric motor (10) of the electromechanical actuator (6) is fastened with a first end face (10e) to the connecting flange (15a) of the actuator housing (15) and is connected with a second end face (10f) via a motor shaft end (10d) to the spring-pressure brake (24), which is fixedly mounted on the actuator housing (15) of the actuator (6). Central buffer coupling (1) to Claim 1 , characterized in that the spring-loaded brake (24) has a magnet housing (24a), a coil (25), compression springs (26), an armature (27), a driving sleeve (28), a flange (29) and a friction disc (20), wherein the armature (27) is connected to the motor cover (23) and thus to the actuator housing (15) via the compression springs (26) and the magnet housing (24a), and wherein the spring-loaded brake (24) is fastened in a rotationally fixed manner to the motor shaft end (10d) of the second end face (10f) of the electric motor (10) via the driving sleeve (28). Central buffer coupling (1) to Claim 3 , characterized in that the driver sleeve (28) of the spring-loaded brake (24) is in positive and/or non-positive engagement with a corresponding counterpart of the flange (29) of the spring-loaded brake (24). Central buffer coupling (1) according to one of the preceding claims, characterized in that a motor axis (10a) of the electric motor (10) runs parallel to a central axis (6a) of the electromechanical actuator (6). Rail vehicle with at least one central buffer coupling (1) according to one of the preceding claims.