COUPLER FOR A MULTI-CAR RAIL VEHICLE

Abstract

 In a coupler (1) of a multi-car light rail vehicle, such as a tram, a coupler head and a pivot bearing having a substantially vertical pivot axis are provided on opposite ends thereof. An actuating cylinder (4) is provided to swivel the coupler (1) about the pivot axis (3A) between a neutral position and a first angular position (ϕ₁). A tensioning device (5) is functionally arranged between the actuating cylinder (4) and a part of the coupler (1) or between the actuating cylinder (4) and a car of the vehicle. In the first angular position (ϕ₁), the coupler head (2) can be pivoted backward about a joint (6) into a parking position. The tensioning device (5) allows the coupler (1) to be swiveled beyond the first angular position (ϕ₁) into a second angular position (ϕ₂).

Description

FIELD OF THE INVENTION

[0001] This invention relates to a coupler for a multi-car rail vehicle, in particular for a light rail vehicle, such as a tram. The invention also relates to a car of a multi-car rail vehicle comprising such a coupler. The coupler of the present invention is particularly intended for the use on a multi-car rail vehicle in which, when the coupler is not in use, i.e. in its uncoupled state, it may be swiveled sideways or even folded away and, when in use, i.e. in its coupled state, it may likewise swivel sideways, namely when the rail vehicle drives along a curvy track. Accordingly, the invention further relates to a method of using the coupler relative to a car of a multi-car rail vehicle.

BACKGROUND OF THE INVENTION

[0002] A device for deflecting a coupler of a multi-car rail vehicle is known from WO 2017/157738 A1, wherein an actuator is provided which is attached to the car body with one of its ends and to the coupler rod of the coupler with its opposite end. The actuator may comprise an actuating cylinder. Using the actuator, the coupler rod and thus the coupler may be actively swiveled about a pivot anchor by which the coupler is pivotably connected to the car body. This way, the deflection device can be used to couple a first car of a multi-car vehicle to a second car of a multi-car vehicle even in a situation where the first car and the second car are not aligned along a straight line but are positioned along a curved track.

[0003] If a coupler is not in use, it is advantageous that the coupler does not protrude from the front of the rail vehicle in order to save space and avoid collision with other parts or people. Therefore, for some rail vehicles it is a requirement to fold the coupler head backward when the coupler is not in use, i.e. in the coupler's uncoupled state, as is further described in EP 3 922 531 A1. In order to fold the coupler head backward and place it in close proximity to the underframe of the rail vehicle, the coupler head is pivotable in relation to a rear portion of the coupler. In some embodiments the coupler is swiveled sideways before or after the coupler head is folded backward.

[0004] In respect of light rail vehicles, such as trams, which need to drive along much tighter curves than regular trains, the sideways swiveling of the coupler during regular use, i.e. in the coupled state, may be more extreme as compared to the sideways swiveling required when the coupler head is to be folded back in its uncoupled state. While it is possible to design the actuating cylinder, which is needed for actively swiveling the coupler sideways in its uncoupled state, sufficiently large so that it can cope with extreme extensions when the rail vehicle passes along tight curves during normal use, the size of such an actuating cylinder may become larger than the available space.

SUMMARY OF THE INVENTION

[0005] It is therefore an object of the present invention to provide a coupler which can be swiveled away from its normal, neutral position, when it is not in use, i.e. in its uncoupled state, and which can be swiveled even further away from its neutral position during normal use, i.e. in its coupled state. It is a further object of the present invention to provide a car of a multi-car rail vehicle having a corresponding coupler. An even further object of the present invention relates to a method of using the coupler on a multi-car rail vehicle.

[0006] Accordingly, a first aspect of the present disclosure relates to a coupler for a multi-car rail vehicle, the coupler comprising a coupler head, at one end thereof, and a pivot bearing having a substantially vertical pivot axis, at an opposite end thereof. The pivot bearing may form part of a pivot anchor, as is generally known in the art. The coupler further comprises an actuating cylinder, wherein one end of the actuating cylinder is connected to a part of the coupler and an opposite end thereof is configured for connection to a car of a multi-car rail vehicle or to a bearing bracket by which the coupler is attachable to a car of a multi-car rail vehicle. The arrangement is such that, in use of the coupler on a multi-car rail vehicle, a change of a length of the actuating cylinder causes the coupler to swivel about the pivot axis in a first direction between a neutral position and a first angular position. The neutral position of the coupler is a position in which a longitudinal axis of the coupler is parallel to a longitudinal axis of the car on which the coupler is mounted. A centering device may be provided to support bringing and/or holding the coupler in the neutral position, as is also generally known in the art. In addition, according to this first aspect of the present disclosure, a tensioning device is provided which is functionally arranged between the actuating cylinder and the part of the coupler or between the actuating cylinder and the car or bearing bracket. In other words, the tensioning device and the actuating cylinder are arranged "in series". This way, any load applied to or applied by the actuating cylinder, such as a pulling or pushing force, is transferred from the actuating cylinder to the tensioning device, and vice versa.

[0007] The actuating cylinder has the primary purpose of enabling automatic swiveling of the coupler into an inactive position or "parking position", e.g. by simply pressing a corresponding button on the driver's control panel. The actuating cylinder preferably comprises a pneumatically driven cylinder, but it may alternatively comprise a hydraulically driven cylinder.

[0008] The tensioning device has the primary effect that any deflection of the coupler from its neutral position toward a pivoted position, which deflection exceeds the range of the actuating cylinder, may be taken up by the tensioning device. Thus, in the coupler's uncoupled state, the coupler may be swiveled actively from the neutral position into the first angular position using the actuating cylinder. Either before or after swiveling the coupler into this first angular position, the coupler head of the coupler may be folded backward toward the pivot axis. By contrast, in the coupler's coupled state, the coupler can swivel even beyond the first angular position into a second angular position, e.g. when the multi-car rail vehicle drives along a tight curve. That is, when the range (or stroke) of the activating cylinder is limited to reach only the first angular position but the curve along which the rail vehicle drives is so tight that such limited range is not enough to allow sufficient swiveling of the coupler, the tensioning device kicks in and may be compressed or extended, as the case may be, in order to allow the coupler to swivel further beyond the first angular position.

[0009] Preferably, in the neutral position of the coupler, the tensioning device is pretensioned. The pretensioning may be a pre-compression or a pre-extension of the tensioning device. In particular, the tensioning device may comprise a spring element, such as a coil spring. Instead of a coil spring, other tensioning means may be used, e.g. tensioning devices comprising an air or gas chamber in which the air/gas may be held in a (pre-)compressed state. As an example, the pretensioned tensioning device may comprise, as a tensioning means, a preloaded biasing element, such as a spring element, in particular a coil spring, which is mounted between two limiting elements, for instance mounted in a compressed state between two plates or mounted in an extended state between two hooks. In a preferred embodiment, the arrangement is such that the biasing element can only be compressed further or extended further, as the case may be, thereby increasing the load on - i.e. the tension of - the biasing element.

[0010] The tension of the pretensioned tensioning device in the coupler's neutral position helps to avoid dynamic effects on the coupler, such as an oscillating swiveling effect, which may otherwise occur due to the elastic biasing effect of the tensioning element when the coupler is actively swiveled, by means of the actuation cylinder, from the neutral position toward the first angular position. That is, because the tensioning element is pretensioned, its elastic properties become effective only after the pretension is overcome.

[0011] The arrangement may be such that the tension of the pretensioned tensioning device may be overcome, such as by further compression or further extension of the tensioning device, as the case may be, only after the swiveling of the coupler has reached a predetermined first angular position. Preferably, the first angular position is the position in which the actuating cylinder has reached a stroke limit. But it is not excluded that in certain arrangements the function of the pretensioning device kicks in at a swiveling angle, i.e. at a first angular position, before the actuating cylinder reaches its stroke limit.

[0012] Preferably, the tension of the pretensioned tensioning device in the neutral position of the coupler is higher than the force which is needed to swivel the coupler about the pivot axis. That is, the tension of the pretensioned tensioning device should be larger than the actuating force which is applied by the actuating cylinder when swiveling the coupler toward the first angular position. Such actuating force depends, on the one hand, on the friction in the pivot joint and, on the other hand, on the lever arm, i.e. on the distance between the pivot axis and the attachment point of the deflecting mechanism (comprising the actuating cylinder and the tensioning device). The lower such friction and the larger such lever arm, the lower is the force needed to swivel the coupler about the pivot axis and, therefore, the smaller can be the pretension and, thus, the dimension of the tensioning device. Preferably, the tension of the pretensioned tensioning device in the neutral position of the coupler is 10 kN or less, more preferably 5 kN or less, most preferably 3 kN or less.

[0013] Accordingly, in an activated state of the actuating cylinder, namely when the coupler is in an uncoupled state and the coupler head is to be swiveled away and possibly folded backward, actuation of the actuating cylinder may cause the coupler to swivel about the pivot axis from the neutral position to the first angular position without any change in the tension of the tensioning device.

[0014] In contrast, in an inactive state of the actuating cylinder, namely during normal use when the coupler is in a coupled state with a corresponding coupler so as to connect two cars of a multi-car rail vehicle, swiveling of the coupler about the pivot axis from the neutral position to the first angular position may coincide with a change of the length of the actuating cylinder, and further swiveling from the first angular position to a second angular position may coincide with an increase of the tension of the pretensioned tensioning device. For this, the coupler or - more specifically - the actuating cylinder may comprise a stroke limit which limits active swiveling of the coupler by means of the actuating cylinder up to the first angular position. Thus, once the coupler has reached the first angular position and the actuating cylinder cannot be extended (or shortened, as the case may be) any further, further swiveling of the coupler toward a second angular position is possible by overcoming the tension of the pretensioned tensioning element and compressing or extending, as the case may be, the tensioning element further, i.e. thereby increasing the tension of the tensioning element.

[0015] In a preferred embodiment, the actuating cylinder is activatable in opposite directions. This way, the actuating cylinder is able to swivel the coupler about the pivot axis not only from its neutral position to the first angular position but also from the first angular position back to the neutral position in which it can be easily coupled with a corresponding second coupler. Again, the return of the coupler to its neutral position may be achieved automatically by means of the actuating cylinder, e.g. by simply pressing a corresponding button on the driver's control panel.

[0016] In a preferred embodiment, the first angular position, i.e. the coupler's parking position, is between 20° and 40°, more preferably about 30°, from the neutral position, and the second angular position, i.e. the coupler's angular position which can be reached in tight curves, is preferably more than 40°, more preferably about 47°, from the neutral position.

[0017] So far, swiveling of the coupler in one direction has been explained, namely from the coupler's neutral position to the first angular position (parking position) and further beyond the first angular position (in tight curves). In order to enable the rail vehicle to drive along tracks which are curved in opposite directions, in particular tight curves, the coupler is configured such that it can swivel about the pivot axis also in a second direction opposite to the first direction. In this situation, swiveling of the coupler in the second direction between the neutral position and a third angular position, more specifically from the neutral position to the third angular position, may likewise coincide with an increase of the tension of the tensioning device.

[0018] Reference is made again to the example above in which the pretensioned tensioning device comprises, as a tensioning means, a preloaded biasing element, such as a spring element, in particular a coil spring, which is mounted between two limiting elements, for instance mounted in a compressed state between two plates or mounted in an extended state between two hooks, and in which the arrangement is such that the biasing element can only be compressed further or extended further, as the case may be, thereby increasing the load on - i.e. the tension of - the biasing element. In this example, when the coupler swivels in the second direction opposite to the first direction, the biasing element is compressed further or extended further, as the case may be, in the opposite direction as compared to when the coupler swivels in the first direction, thereby likewise increasing the load on - i.e. the tension of - the biasing element.

[0019] In the embodiments described so far, where the actuating cylinder is designed to deflect the coupler from the neutral position into the parking position only toward one side of the coupler's neutral position, i.e. only in the first direction, such further compression or extension of the biasing element in the opposite direction would begin as soon as the coupler starts swiveling from the neutral position toward the third angular position, i.e. in the second direction. However, the present disclosure is not limited to this embodiment and may analogously be applied to alternative embodiments in which parking positions are provided for the coupler on opposite sides relative to the coupler's neutral position. In such alternative embodiments, the further compression or extension of the biasing element in the opposite direction would begin only after the actuating cylinder (or a different actuating cylinder) has reached a corresponding (second) stroke limit.

[0020] Preferably, the tensioning device is located on one side relative to a first virtual plane which connects the coupler head and the pivot axis, whereas the actuating cylinder is located on an opposite side relative to the first virtual plane, in which this first virtually plane is preferably a vertical plane. This way, the actuating cylinder and the tensioning device can be arranged substantially in one line, in which case the overall deflecting mechanism has a substantial length, without protruding too much from the major longitudinal axis of the coupler head. That is, arranging the actuating cylinder and the tensioning device side by side, such as one above the other, may render the overall deflecting mechanism bulky so that it may become difficult to arrange it, e.g. on the underside of the coupler, whereas, when the actuating cylinder and the tensioning device are arranged substantially aligned, the overall deflecting mechanism becomes long but slim, in which case it may be easier to arrange it, e.g. on the underside of the coupler, namely preferably such that the tensioning device is located on one side of the longitudinal axis of the coupler and the actuating cylinder is located on the opposite side of the longitudinal axis.

[0021] Further preferably, both the tensioning device and the actuating cylinder are located above or below a second virtual plane, which is a horizontal plane, connecting the coupler head and the pivot axis. This way, a vertical extension of the overall deflecting mechanism may be kept small.

[0022] The coupler may further comprise a centering device which, as such, is generally known in the art. The centering device may be configured to have an active state and an inactive state, e.g. comprising a pneumatic or hydraulic system, wherein, in the active state, the centering device supports swiveling of the coupler toward the neutral position.

[0023] Furthermore, the coupler may comprise a joint between the pivot axis and the coupler head which is configured for enabling the coupler head to be folded backward toward the pivot axis, which is likewise generally known in the art (EP 3 922 531 A1). In particular, the coupler head may comprise a coupling rod between the coupler head and pivot anchor, wherein the joint divides the coupling rod into a front section bearing the coupler head and a rear section which connects to the pivot anchor.

[0024] A second aspect of the present disclosure relates to a car of a multi-car rail vehicle which comprises a coupler of the type discussed above. Accordingly, a pivot anchor in which the pivot bearing of the coupler is realized may be attached to the body of the car either directly or via a mounting bracket arranged between the pivot anchor and the car body.

[0025] A third aspect of the present disclosure relates to a method of using a coupler of the type discussed above on a car of a multi-car rail vehicle. Accordingly, when the coupler is in an uncoupled state, the coupler may be swiveled sideways relative to the car into the first angular position, i.e. the parking position, using the actuating cylinder. Preferably, the coupler head of the coupler is folded backward toward the pivot axis, whose backward-folding may occur either before or after the coupler is swiveled between its neutral position and the first angular position. The mechanism for pivoting the coupler head backward may likewise be automatic such that, e.g. pressing a button on the driver's control panel would be sufficient to pivot the coupler head back and forth.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The foregoing summary as well as the following detailed description of preferred embodiments will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, reference is made to the drawings. The scope of the disclosure, however, is not limited to the specific embodiments disclosed in the drawings. In the drawings:

Fig. 1 to 5 are schematic views of a coupler according to a first embodiment of the present disclosure in different positions,

Fig. 6 shows a modification of the first embodiment of Figs. 1 to 5,

Figs. 7 to 11 are schematic views of a coupler according to a second, more detailed embodiment of the present disclosure in different positions,

Figs. 12A to 12C show a concrete example of the tensioning device, and

Figs. 13 to 19 are different views of a concrete coupler according to an even more detailed third embodiment of the present disclosure, similar to the first embodiment.

DETAILED DESCRIPTION

[0027] Figs. 1 to 5 are schematic views of a coupler 1 according to a first embodiment of the present disclosure in different positions. The coupler 1 comprises a coupler head 2 at one end thereof and a pivot bearing 3 at an opposite end thereof. The pivot bearing 3 has a substantially vertical pivot axis which extends vertically relative to the plane in which the schematic view of the coupler 1 is illustrated. The pivot bearing 3 may form part of a pivot anchor by which the coupler 1 is mounted to a car 100 or car body of a multi-car rail vehicle or to a bearing bracket by which the coupler is mounted to the car 100 or car body. The coupler 1 further comprises an actuating cylinder 4. One end of the actuating cylinder 4 is connected to a part of the coupler 1, such as to the coupler rod 7, arranged between the coupler head 2 and pivot bearing 3. The other end of the actuating cylinder 4 is configured for connection to the car 100 or bearing bracket by which the coupler 1 may be attached to the car 100. Finally, there is further provided a tensioning device 5 which is functionally arranged between the actuating cylinder 4 and the part of the coupler 1, i.e. the rod, although this is not directly derivable from the illustration according to Fig. 1. That is, the actuating cylinder 4 is not directly connected to the rod 7 but it is connected to the tensioning device 5, and it is the tensioning device 5 which is connected to the rod 7. In any case, the arrangement is such that a change of the length of the actuating cylinder 4 causes the coupler 1 to swivel about the pivot bearing 3.

[0028] More specifically, Fig. 1 shows a neutral position of the coupler 1 in which the coupler head 2 extends straight away from the car 100. The actuating cylinder comprises a piston 41 and a piston rod 42. In this embodiment, the piston rod 42 extends from the actuating cylinder 4 in the neutral position of the coupler 1. Upon actuation of the actuating cylinder 4, the piston 41 moves inside the cylinder 4 such that the piston rod 42 is drawn into the actuating cylinder 4, thereby reducing the length of the actuating cylinder 4. The actuating cylinder 4 is preferably a pneumatic actuating cylinder but may alternatively be designed as a hydraulic actuating cylinder. There is a stroke limit 43 which limits the stroke of the piston 41. Fig. 2 shows the position of the coupler 1 at maximum stroke of the pneumatic cylinder 4, i.e. when the piston 41 has reached the stroke limit 43. Thus, by actuation of the actuating cylinder 4, the coupler 1 can be pivoted into a first angular position indicated as ϕ₁.

[0029] As can be seen from Fig. 2, the biasing element 51 of the tensioning device 5 is not affected by such movement of the coupler 1. In particular, it does not matter whether the actuating cylinder 4 is in an active state and actively moved from the neutral position shown in Fig. 1 to the first angular position shown in Fig. 2 or whether the actuating cylinder 4 is inactive, i.e. not under any pressure, and such movement of the coupler 1 occurs during regular use in the coupled state of the coupler 1 when the car 100 forms part of a multi-car rail vehicle and drives along a curved track.

[0030] However, in the uncoupled state, the coupler 1 may be actively pivoted into the angled position shown in Fig. 2 by pressurizing the actuating cylinder 4. Either before or after such sideways pivoting of the coupler 1, the coupler head 2 may be folded backward about the joint 6 which separates the coupler rod 7 into a front section 7a and a rear section 7b. This is shown in Fig. 3 and further described in EP 3 922 531 A1. By pressurizing the actuating cylinder 4 in the opposite direction such that the piston rod 42 returns into its original position of Fig. 1, the coupler 1 may be brought back to its neutral position.

[0031] During regular use, i.e. when the coupler 1 is coupled to a corresponding second coupler of a second car and the car moves along a curvy track, it may happen that the coupler 1 is deflected even further than the first angular position ϕ₁ shown in Fig. 2. That is, a preferred first angular position ϕ₁ for folding away the coupler head 2 may be 30°, whereas a second angular position ϕ₂ of the coupler 1 during regular use may have to cover up to 47° in both directions relative to the neutral position of the coupler 1 as shown in Fig. 1. In this regard, Fig. 4 shows the situation when the coupler 1 is moved beyond the first angular position ϕ₁ into a second angular position ϕ₂, wherein ϕ₂ > ϕ₁. The actuating cylinder 4 had already reached its maximum stroke when the coupler 1 was in the first angular position ϕ₁. Therefore, the additional swiveling of the coupler 1 between the first angular position ϕ₁ and a second angular position ϕ₂ is taken up by the biasing element 51 of the tensioning device 5. That is, such further pivoting of the coupler 1 about the pivot joint 3 causes the biasing element 51, which may be a coil spring, to be compressed.

[0032] Fig. 5 shows the coupler 1 swiveled to the opposite maximum second angular position ϕ₃, wherein ϕ₃ = -ϕ₂. During the motion of the coupler head 1 from the second angular position ϕ₂ into the third angular position ϕ₃ = -ϕ₂, namely during normal use in a coupled state of the coupler 1, first the biasing element 51 will expand again into its normal state until the first angular position ϕ₁ is reached. Further movement from the first angular position ϕ₁ to the neutral position causes the piston 41 of the actuating cylinder 4 to return to its original position as shown in Fig. 1. In the embodiment shown in Figs. 1 to 5, any further movement of the piston 41 of the actuating cylinder 4 beyond the neutral position is limited by a second stroke limit 44. Therefore, as of the point when the coupler 1 pivots beyond its neutral position toward the third angular position ϕ₃, such movement is taken up by the biasing element 51 of the tensioning device 5. In the particular embodiment shown, the biasing element 51 in the form of a coil spring is compressed in the opposite direction as compared to the compression of the biasing element 51 when the coupler 1 pivots in the first direction (Fig. 4).

[0033] Of course, the principle behind this technical solution can be varied in many ways. For instance, instead of arranging the tensioning device 5 functionally between the actuating cylinder 4 and a part (rod 7) of the coupler 1, the tensioning device 5 may be placed functionally between the actuating cylinder 4 and the car 100 or a mounting bracket or other component by which the coupler 1 is fixedly mounted to the car 100. Likewise, as shown in Fig. 6, the distance A between the attachment point 8 of the tensioning device 5/actuating cylinder 4 on the part (rod 7) and pivot axis 3A of the pivot bearing 3 is not critical as long as the attachment point 8 is between the pivot bearing 3 and joint 6, i.e. A < B. However, the distance A defines a lever arm for the actuating cylinder 4 and, therefore, the shorter the distance A is, the less powerful needs to be actuating cylinder 4. Further, as can also be seen from Fig. 6, it is not critical where the actuating cylinder 4/tensioning device 5 is fixedly attached relative to the car 100 or relative to the pivot bearing 3. The dimension C illustrated in Fig. 6 may be larger or smaller than the distance A (lever arm) and is preferably close to the distance A so that maximum use of the power of the actuating cylinder 4 can be achieved.

[0034] Likewise, although it is described in relation to Figs. 1 to 5 that the biasing element 51 of the tensioning device 5 is compressed in certain situations, it is clear to the skilled person that in a reversed kinematic arrangement the biasing element 51 may be extended rather than compressed when increasing the load on the biasing element 51. Also, the biasing element 51 does not necessarily need to be a mechanical spring element, but a gas chamber may be used as the biasing "element" 51 instead.

[0035] In addition, while it may be preferable to arrange the actuating cylinder 4 and the tensioning device 5 on opposite sides of a vertical plane Q, as shown in Fig. 1, where plane Q is defined in that it is vertical, on the one hand, and connects the coupler head 2 and pivot axis 3A of the pivot bearing 3, on the other hand, both the actuating cylinder 4 and the tensioning device 5 may be arranged on the same side of the vertical plane Q, or one or both of the actuating cylinder 4 and the tensioning device 5 may be arranged across such vertical plane Q. Even further, the actuating cylinder 4 and the tensioning device 5 may be arranged below a horizontal plane connecting the coupler head 2 and pivot axis 3A of the pivot bearing 3, i.e. above or below the coupler rod 7.

[0036] Figs. 7 to 11 show schematic views of a coupler according to a second embodiment in somewhat more detail as compared to the sketches in Figs. 1 to 5. In this second embodiment, both the actuating cylinder 4 and the tensioning device 5 are arranged on the same side of the vertical plane Q. A pressure pump 9 is provided to urge the piston 41 toward the stroke limit 43 by accordingly increasing the pressure on one side of the piston 41. A piston rod 42 is fixedly connected to the tensioning device 5 which in turn is connected to the coupler rod 7 and the attachment point 8. Thus, when the piston 41 is actively moved toward the stroke limit 44, the tensioning device 5 is pulled in the same direction, thereby likewise pulling the coupler rod 7 into the same direction so that, consequently, the coupler 1 swivels about the pivot axis 3A of the pivot bearing 3.

[0037] In order to avoid that the biasing element 51 of the tensioning device 5 starts to oscillate during such operation and, thus, the coupler 1 starts to oscillate about the pivot axis 3A, the tensioning device is pretensioned. More specifically, the biasing element 51 is mounted between two plates 52A and 52B which are held in a housing 53 so as to limit the maximum distance between the plates 52A, 52B. The term "increasing" is to be understood in the broadest sense. While it may be a substantially closed box, it may likewise be an open scaffold. Similarly, the term plate is to be understood in its broadest sense, i.e. it does not need to be flat nor continuous but may have any suitable shape serving the required function. A plunger 54 which is attached to the rear section 7B of the coupler rod 7 extends into the housing 53 and through the plates 52A and 52B, wherein carriers 54A and 54B are arranged on opposite sides of the plates 52A, 52B so as to accommodate the plates 52A, 52B between the carriers 54A, 54B. Since the biasing element 51, here in the form of a coil spring, is pretensioned in this arrangement between the two plates 52A, 52B, any movement of the piston 41 of the actuating cylinder 4 causes the plunger 54 and, thus, the entire tensioning device 5, to follow such movement of the piston 41 without any change in the tension of the biasing element 51, provided that the frictional forces in the pivot bearing 3 (and strictly speaking also the frictional forces on the attachment point 8) that need to be overcome in order to swivel the coupler 1 about the pivot axis 3A are lower than the tension of the pretensioned biasing element 51.

[0038] Figs. 8 to 11 show again the swivel motion of the coupler 1 about the pivot bearing 3, similar to Figs. 1 to 5. Accordingly, as shown in Fig. 8, when the coupler 1 swivels about the pivot bearing 3 in a first direction by an angle ϕ, either actively in its uncoupled state or passively in its coupled state, the piston 41 of the actuating cylinder 4 moves a distance Δx(ϕ), whereas the biasing element 51 of the pretensioned tensioning device 5 is not affected at all. At a first angular position ϕ₁, as shown in Fig. 9, the piston 41 has moved a distance Δx(ϕ₁) and reached the stroke limit 43. This is the position in which the coupler head 3 may be swiveled away about the joint 6 into a parking position. Further swiveling of the coupler 1 about the pivot bearing 3 causes the plunger 54 to move into the housing 53, thereby displacing the plate 52A by means of its carrier 54A by a distance Δx(ϕ₂-ϕ₁), as shown in Fig. 10. In this situation, the biasing element 51 is further compressed between the two plates 52A, 52B inside the housing 53. Fig. 11 shows the coupler 1 swiveled in the opposite direction about the pivot bearing 3 into a third angular position ϕ₃ opposite the second angular position ϕ₂. The piston 41 in the actuating cylinder 4 has returned to its original (neutral) position and, furthermore, the plunger 54 has been pulled out from the housing 53, thereby moving the carrier 54B inside the housing 53 about a distance Δx(ϕ₃) toward the carrier 54A. The distance Δx(ϕ₃) may be different, in particular larger, than the distance Δx(ϕ₂-ϕ₁). Again, the biasing element 51 is further compressed between the two plates 52A, 52B, but in an opposite direction as compared to the situation shown in Fig. 10.

[0039] Figures 12A to 12C show a concrete example of a tensioning device 5. The tensioning device 5 comprises a cylindrical housing 53 in which a biasing element 51, more specifically a coil spring, most specifically a stock dye spring, is mounted so as to be held between a first plate 52A and second plate 52B. A plunger 54 extends through both plates 52A, 52B and out of the housing 53. The plunger 54 has a first carrier 54A holding the first plate 52A from one external side and a second carrier 54B holding the second plate 52B from an opposite external side so that the plates 52A, 52B are arranged between the carriers 54A, 54B. A retaining ring 55 limits the movement of the first plate 52A inside the housing 53, and an end cap 56 may be provided to close the housing 53. In addition, draining holes 57 may be provided so that any water entering the housing 53 may escape. The free end of the plunger 54 extending from the housing 53 has an eye 58 for a ball joint in order to connect the tensioning device 5 to a part of the coupler 1, such as the coupler rod 7. In addition, the tensioning device 5 has a mounting section 59 configured for mounting an actuating cylinder 4 to the tensioning device 5.

[0040] While Fig. 12A shows the tensioning device 5 in its neutral position with the pretensioned biasing element 51 having its maximum extension between the two plates 52A, 52B, Fig. 12B shows the tensioning device 5 in a first extended position in which the biasing element 51 is compressed in a first direction and the plunger 54 extends further from the housing 53 as compared to the tensioning device's neutral position. In contrast, in Fig. 12C the biasing element 51 is further compressed into a second direction opposite the first direction and the plunger 54 has moved further into the housing 53 as compared to the tensioning device's neutral position. The states of the actuating cylinder 4 as shown in Figs. 12B and 12C relate to the two maximum angular positions of the coupler head 1, i.e. the second angular position ϕ₂ (e.g. 47°) and the third angular position ϕ₃ (e.g. -47°).

[0041] Figs. 13 to 19 are different views of a concrete coupler 1 according to an even more detailed third embodiment, which embodiment is similar to the first embodiment in Figs. 1 to 5. Figs. 13 to 19 each show both a perspective view of the coupler 1 and a corresponding view of only the actuating cylinder 4 and the tensioning device 5 in cross section.

[0042] Accordingly, the coupler 1 comprises a coupler rod 7 with a coupler head 2 on one end of the coupler rod 7 and a pivot anchor comprising a pivot bearing 3 on the other end of the coupler rod 7. A joint 6 divides the coupler rod 7 into a front section 7A and rear section 7B. The rear section 7B may have many different shapes and functions. In the embodiment shown, the rear section 7B comprises an energy dissipating member 7C which absorbs energy in a destructive way in the case of an accident in order to prevent other components of the coupler from damage. On the underside of the pivot anchor, there is an attachment point 8 in the form of a pin to which the deflecting unit comprising the actuating cylinder 4 and the tensioning device 5 is rotatably mounted. In the embodiment shown, it is the tensioning device 5 which is attached to the pivot anchor at the attachment point 8, whereas the actuating cylinder 4 is pivotably attached to a mounting bracket 101 which, in turn, is fixedly attached to the car 100. The pivot axis 3A of the pivot bearing 3 is arranged at a distance A from the attachment point 8, as can best be seen in Fig. 19A.

[0043] As further shown in Fig. 13A, a centering device 10 is provided to urge the pivot anchor and, thus, the coupler 1 into the neutral position. Centering devices of this type are generally known to the skilled person in the art. They typically include a pneumatic cylinder which, in its active state, supports such a centering function. When the coupler 1 is swiveled sideways by means of the actuating cylinder 4 into the first angular position in order for the coupler head 2 to be folded back, the centering device 10 is in its inactive state, i.e. the pneumatic cylinder thereof is pressureless.

[0044] Figs. 13A to 15B illustrate the folding sequence of the uncoupled coupler 1 from the neutral position shown in Fig. 13A, through a first angular position shown in Fig. 14A to a folded position shown in Fig. 15A. In the neutral position, the (pneumatic) actuating cylinder is in its extended position with the piston rod 42 extending from the actuating cylinder 4, whereas the tensioning device 5 is in a neutral state, as illustrated in Fig. 13B. In the first angular position shown in Fig. 14A, the actuating cylinder has actively swiveled the coupler to the folding angle (ϕ₁). In this state the piston rod 42 is retracted into the actuating cylinder 4 and the tensioning device 5 is still in its neutral state, as illustrated in Fig. 14B. Finally, when the coupler 1 is in the first angular position (ϕ1) shown in Fig. 14A, the coupler head 2 is folded backward toward the car 100 via the joint 6, as shown in Fig. 15A. In this position, the actuating cylinder 4 is still active, but the folding action has no effect on the state of the actuating cylinder 4 nor on the state of the tensioning device 5, as illustrated in Fig. 15B.

[0045] Figs. 16A to 19B illustrate the deflection of the coupler 1 during normal use, i.e. in a situation where the coupler head 2 is coupled to a corresponding coupler head 2' of a coupler of a second car, as shown in Fig. 16A. Fig. 16A illustrates the neutral position of the coupler 1 which differs from the state shown in Fig. 13A only in that the actuating cylinder 4 is inactive. Fig. 17A illustrates the coupler 1 in its coupled state when it has been swiveled to the angular position corresponding to the first angular position shown in Fig. 14A. Again, the state of the actuating cylinder 4 and the tensioning device 5 is exactly the same as in Figs. 14A, 14B, i.e. the piston rod 42 is retracted into the actuating cylinder 4, with the sole difference that the actuating cylinder 4 is inactive. Fig. 18A shows the coupler 1 in the coupled state in a second angular position (ϕ₁) beyond the first angular position of Fig. 17A. In this second angular position, the (inactive) actuating cylinder 4 is still in its retracted state, but the pretensioned biasing element 51 of the tensioning device 5 is further compressed by means of the plunger 54 which has been pulled out of the housing 53, thereby advancing the plate 52B so as to compress the biasing element 51 against the other plate 52A. In this perspective view, due to the particular angled position of the coupler 1, it can be seen that the attachment point 8 to which the tensioning device 5 is attached, is at a distance A of the pivot axis 3A of the pivot anchor's pivot bearing 3. This is even better visible in Fig. 19A which shows the coupler 1 swiveled about the pivot axis 3A in the opposite direction into a third angular position (ϕ₃) in its coupled state, i.e. during normal operation. Again, the pneumatic cylinder is inactive but fully extended, i.e. the piston rod 42 extends from the actuating cylinder 4 in the same way as in the neutral position shown in Figs. 16A, 16B. However, in the third angular position of the coupler 1 as shown in Fig. 19A, the pretensioned biasing element 51 is further compressed inside the housing 53 by means of the plunger 54 which is urged into the housing 53, thereby urging the plate 52A toward the plate 52B, as illustrated in Fig. 18B.

[0046] Preferred aspects of the present disclosure are specified in the following paragraphs, whereas the scope of protection of the present invention is defined by the appended claims:

1. A coupler (1) for a multi-car rail vehicle, in particular for a light rail vehicle such as a tram, the coupler comprising a coupler head (2), at one end thereof, and a pivot bearing (3) having a substantially vertical pivot axis (3A), at an opposite end thereof, and further comprising an actuating cylinder (4), one end thereof being connected to a part of the coupler (1) and an opposite end thereof being configured for connection to a car (100) of a multi-car rail vehicle or to a bearing bracket by which the coupler is attachable to a car of a multi-car rail vehicle, wherein the arrangement is such that, in use of the coupler (1) on a multi-car rail vehicle, a change of a length of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) in a first direction between a neutral position and a first angular position (ϕ₁), characterized by a tensioning device (5) functionally arranged between the actuating cylinder (4) and the part of the coupler (1) or between the actuating cylinder (4) and the car (100) or bearing bracket (101).

2. The coupler according to paragraph 1, wherein, in the neutral position of the coupler (1), the tensioning device (5) is pretensioned.

3. The coupler according to paragraph 2, wherein the tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is in the form of a pre-compression or a pre-extension of the tensioning device (5).

4. The coupler according to paragraph 2 or 3, wherein a tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is higher than a force which is needed to pivot the coupler (1) about the pivot axis (3A).

5. The coupler according to paragraph 4, wherein the tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is 10 kN or less.

6. The coupler according to paragraph 4, wherein the tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is 5 kN or less.

7. The coupler according to paragraph 4, wherein the tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is 3 kN or less.

8. The coupler according to any one of paragraphs 2 to 7, wherein the pretensioned tensioning device (5) comprises a preloaded biasing element (51) which is mounted between two limiting elements (52A, 52B) either in a compressed state or in an extended state.

9. The coupler according to paragraph 8, wherein the arrangement is such that the biasing element (51) can only be compressed further or extended further, as the case may be, thereby increasing the load on the biasing element (51).

10. The coupler according to any one of the preceding paragraphs, wherein, in an activated state of the actuating cylinder (4), actuation of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) from the neutral position to the first angular position (ϕ₁) without any change in the tension of the tensioning device (5).

11. The coupler according to any one of the preceding paragraphs, wherein, in an inactive state of the actuating cylinder (4), swiveling of the coupler (1) about the pivot axis (3A) from the neutral position to the first angular position (ϕ₁) coincides with a change of the length of the actuating cylinder (4) and further swiveling from the first angular position (ϕ₁) to a second angular position (ϕ₂) coincides with an increase of the tension of the tensioning device (5).

12. The coupler according to any one of the preceding paragraphs, comprising a stroke limit which limits active swiveling of the coupler (1) by means of the actuating cylinder (4) up to the first angular position (ϕ₁).

13. The coupler according to any one of the preceding paragraphs, wherein the actuating cylinder (4) is activatable in opposite directions so as to enable the actuating cylinder (4) to cause the coupler (1) to swivel about the pivot axis (3A) both from the neutral position to the first angular position (ϕ₁) and from the first angular position (ϕ₁) to the neutral position.

14. The coupler according to any one of the preceding paragraphs, wherein the tensioning device (5) is a biasing element (51).

15. The coupler according to paragraph 14, wherein the spring element is a coil spring.

16. The coupler according to any one of the preceding paragraphs, wherein the first angular position (ϕ₁) is between 20° and 40° from the neutral position.

17. The coupler according to paragraph 16, wherein the first angular position (ϕ₁) is 30° from the neutral position.

18. The coupler according to any one of the preceding paragraphs, wherein the second angular position (ϕ₂) is more than 40° from the neutral position.

19. The coupler according to paragraph 18, wherein the second angular (ϕ₂) position is 47° from the neutral position.

20. The coupler according to any one of the preceding paragraphs, wherein the arrangement is such that swiveling of the coupler (1) about the pivot axis (3A) in a second direction opposite to the first direction between the neutral position and a third angular position (ϕ₃) coincides with an increase of the tension of the tensioning device (5).

21. The coupler according to any one of the preceding paragraphs, wherein the tensioning device (5) is located on one side relative to a first virtual plane (Q) which connects the coupler head (2) and the pivot axis (3A) and the actuating cylinder (4) is located on an opposite side relative to the first virtual plane (A).

22. The coupler according to paragraph 21, wherein the first virtual plane (Q) is vertical.

23. The coupler according to any one of the preceding paragraphs, wherein both the tensioning device (5) and the actuating cylinder (4) are located above or below a second, horizontal virtual plane connecting the coupler head (2) and the pivot axis (3A).

24. The coupler according to any one of the preceding paragraphs, comprising a centering device configured to have an active state and an inactive state, wherein, in the active state, the centering device supports swiveling of the coupler (1) toward the neutral position.

25. The coupler according to any one of the preceding paragraphs, comprising a joint (6) between the pivot axis (3A) and the coupler head (2), the joint (6) being configured for enabling the coupler head (2) to be folded backward toward the pivot axis (3A).

26. A car (100) of a multi-car rail vehicle comprising a coupler (1) according to any one of the preceding paragraphs.

27. A method of using the coupler according to any one of paragraphs 1 to 25 on a car (100) of a multi-car rail vehicle, wherein, when the coupler (1) is in an uncoupled state, the coupler (1) is swiveled sideways relative to the car (100) into the first angular position (ϕ₁) using the actuating cylinder (4).

28. The method according to paragraph 27, wherein the coupler head (2) of the coupler (1) is folded backward toward the pivot axis (3A).

Claims

1. A coupler (1) for a multi-car rail vehicle, in particular for a light rail vehicle such as a tram, the coupler comprising a coupler head (2), at one end thereof, and a pivot bearing (3) having a substantially vertical pivot axis (3A), at an opposite end thereof, and further comprising an actuating cylinder (4), one end thereof being connected to a part of the coupler (1) and an opposite end thereof being configured for connection to a car (100) of a multi-car rail vehicle or to a bearing bracket by which the coupler is attachable to a car of a multi-car rail vehicle, wherein the arrangement is such that, in use of the coupler (1) on a multi-car rail vehicle, a change of a length of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) in a first direction between a neutral position and a first angular position (ϕ₁), characterized by a tensioning device (5) functionally arranged between the actuating cylinder (4) and the part of the coupler (1) or between the actuating cylinder (4) and the car (100) or bearing bracket (101).

2. The coupler according to claim 1, wherein, in the neutral position of the coupler, the tensioning device (5) is pretensioned, wherein preferably the tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is in the form of a pre-compression or a pre-extension of the tensioning device (5).

3. The coupler according to claim 2, wherein a tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is higher than a force which is needed to pivot the coupler (1) about the pivot axis (3A), wherein preferably the tension of the pretensioned tensioning device (5) in the neutral position of the coupler (1) is 10 kN or less, more preferably 5 kN or less, most preferably 3 kN or less.

4. The coupler according to claim 2 or 3, wherein the pretensioned tensioning device (5) comprises a preloaded biasing element (51) which is mounted between two limiting elements (52A, 52B) either in a compressed state or in an extended state, wherein preferably the arrangement is such that the biasing element (51) can only be compressed further or extended further, as the case may be, thereby increasing the load on the biasing element (51).

5. The coupler according to any one of the preceding claims, wherein, in an activated state of the actuating cylinder (4), actuation of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) from the neutral position to the first angular position (ϕ₁) without any change in the tension of the tensioning device (5).

6. The coupler according to any one of the preceding claims, wherein, in an inactive state of the actuating cylinder (4), swiveling of the coupler (1) about the pivot axis (3A) from the neutral position to the first angular position (ϕ₁) coincides with a change of the length of the actuating cylinder (4) and further swiveling from the first angular position (3A) to a second angular position (ϕ₂) coincides with an increase of the tension of the tensioning device (5).

7. The coupler according to any one of the preceding claims, comprising a stroke limit (43) which limits active swiveling of the coupler (1) by means of the actuating cylinder (4) up to the first angular position (ϕ₁).

8. The coupler according to any one of the preceding claims, wherein the actuating cylinder (4) is activatable in opposite directions so as to enable the actuating cylinder (4) to cause the coupler (1) to swivel about the pivot axis (3A) both from the neutral position to the first angular position (ϕ₁) and from the first angular position (ϕ₁) to the neutral position.

9. The coupler according to any one of the preceding claims, wherein the tensioning device (5) comprises a biasing element (51), preferably a coil spring.

10. The coupler according to any one of the preceding claims, wherein one or both of:

- the first angular position (ϕ₁) is between 20° and 40°, preferably 30°, from the neutral position and

- the second angular position (ϕ₂) is more than 40°, preferably 47°, from the neutral position.

11. The coupler according to any one of the preceding claims, wherein the arrangement is such that swiveling of the coupler (1) about the pivot axis (3A) in a second direction opposite to the first direction between the neutral position and a third angular position (ϕ₃) coincides with an increase of the tension of the tensioning device (5).

12. The coupler according to any one of the preceding claims, wherein one or both of:

- the tensioning device (5) is located on one side relative to a first virtual plane (Q) which connects the coupler head (2) and the pivot axis (3A) and the actuating cylinder (4) is located on an opposite side relative to the first virtual plane (Q), wherein preferably the first virtual plane (Q) is vertical, and

- both the tensioning device (5) and the actuating cylinder (4) are located above or below a second, horizontal virtual plane connecting the coupler head (2) and the pivot axis (3A).

13. The coupler according to any one of the preceding claims, comprising a centering device (10) configured to have an active state and an inactive state, wherein, in the active state, the centering device (10) supports swiveling of the coupler (1) toward the neutral position.

14. The coupler according to any one of the preceding claims, comprising a joint (6) between the pivot axis (3A) and the coupler head (2), the joint (6) being configured for enabling the coupler head (2) to be folded backward toward the pivot axis (3A).

15. A car (100) of a multi-car rail vehicle comprising a coupler (1) according to any one of the preceding claims.

16. A method of using the coupler (1) according to any one of claims 1 to 14 on a car (100) of a multi-car rail vehicle, wherein, when the coupler (1) is in an uncoupled state, the coupler (1) is swiveled sideways relative to the car (100) into the first angular position (ϕ₁) using the actuating cylinder (4), wherein preferably the coupler head (2) of the coupler (1) is folded backward toward the pivot axis (3A).

Amended claims

Amended claims in accordance with Rule 137(2) EPC.

1. A coupler (1) for a multi-car rail vehicle, in particular for a light rail vehicle such as a tram, the coupler comprising a coupler head (2), at one end thereof, a pivot bearing (3) having a substantially vertical pivot axis (3A), at an opposite end thereof, and a centering device (10) configured to have an active state and an inactive state, wherein, in the active state, the centering device (10) supports swiveling of the coupler (1) toward the neutral position, and further comprising, in addition to the centering device, an actuating cylinder (4), one end thereof being connected to a part of the coupler (1) and an opposite end thereof being configured for connection to a car (100) of a multi-car rail vehicle or to a bearing bracket by which the coupler is attachable to a car of a multi-car rail vehicle, wherein the arrangement is such that, in use of the coupler (1) on a multi-car rail vehicle, a change of a length of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) in a first direction between a neutral position and a first angular position (ϕ₁), characterized by a tensioning device (5) functionally arranged between the actuating cylinder (4) and the part of the coupler (1) or between the actuating cylinder (4) and the car (100) or bearing bracket (101).

2. A coupler (1) for a multi-car rail vehicle, in particular for a light rail vehicle such as a tram, the coupler comprising a coupler head (2), at one end thereof, and a pivot bearing (3) having a substantially vertical pivot axis (3A), at an opposite end thereof, and further comprising an actuating cylinder (4), one end thereof being connected to a part of the coupler (1) and an opposite end thereof being configured for connection to a car (100) of a multi-car rail vehicle or to a bearing bracket by which the coupler is attachable to a car of a multi-car rail vehicle, wherein the arrangement is such that, in use of the coupler (1) on a multi-car rail vehicle, a change of a length of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) in a first direction between a neutral position and a first angular position (ϕ₁), wherein a tensioning device (5) functionally arranged between the actuating cylinder (4) and the part of the coupler (1) or between the actuating cylinder (4) and the car (100) or bearing bracket (101), wherein, in the neutral position of the coupler, the tensioning device (5) is pre-tensioned in the form of a pre-compression or a pre-extension of the tensioning device (5), wherein the pre-tensioned tensioning device (5) comprises a pre-loaded biasing element (51) which is mounted between two limiting elements (52A, 52B) either in a compressed state or in an extended state, characterized in that the arrangement is such that the biasing element (51) can only be compressed further or extended further, as the case may be, thereby increasing the load on the biasing element (51).

3. A coupler (1) for a multi-car rail vehicle, in particular for a light rail vehicle such as a tram, the coupler comprising a coupler head (2), at one end thereof, and a pivot bearing (3) having a substantially vertical pivot axis (3A), at an opposite end thereof, and further comprising an actuating cylinder (4), one end thereof being connected to a part of the coupler (1) and an opposite end thereof being configured for connection to a car (100) of a multi-car rail vehicle or to a bearing bracket by which the coupler is attachable to a car of a multi-car rail vehicle, wherein the arrangement is such that, in use of the coupler (1) on a multi-car rail vehicle, a change of a length of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) in a first direction between a neutral position and a first angular position (ϕ₁), wherein a tensioning device (5) functionally arranged between the actuating cylinder (4) and the part of the coupler (1) or between the actuating cylinder (4) and the car (100) or bearing bracket (101), characterized in that the tensioning device (5) is located on one side relative to a first virtual plane (Q) which connects the coupler head (2) and the pivot axis (3A) and the actuating cylinder (4) is located on an opposite side relative to the first virtual plane (Q), wherein preferably the first virtual plane (Q) is vertical.

4. The coupler according to claim 1 or 3, wherein, in the neutral position of the coupler, the tensioning device (5) is pre-tensioned, wherein preferably the tension of the pre-tensioned tensioning device (5) in the neutral position of the coupler (1) is in the form of a pre-compression or a pre-extension of the tensioning device (5).

5. The coupler according to claim 4, wherein a tension of the pre-tensioned tensioning device (5) in the neutral position of the coupler (1) is higher than a force which is needed to pivot the coupler (1) about the pivot axis (3A), wherein preferably the tension of the pre-tensioned tensioning device (5) in the neutral position of the coupler (1) is 10 kN or less, more preferably 5 kN or less, most preferably 3 kN or less.

6. The coupler according to claim 4 or 5, wherein the pre-tensioned tensioning device (5) comprises a preloaded biasing element (51) which is mounted between two limiting elements (52A, 52B) either in a compressed state or in an extended state, wherein preferably the arrangement is such that the biasing element (51) can only be compressed further or extended further, as the case may be, thereby increasing the load on the biasing element (51).

7. The coupler according to any one of the preceding claims, wherein, in an activated state of the actuating cylinder (4), actuation of the actuating cylinder (4) causes the coupler (1) to swivel about the pivot axis (3A) from the neutral position to the first angular position (ϕ₁) without any change in the tension of the tensioning device (5).

8. The coupler according to any one of the preceding claims, wherein, in an inactive state of the actuating cylinder (4), swiveling of the coupler (1) about the pivot axis (3A) from the neutral position to the first angular position (ϕ₁) coincides with a change of the length of the actuating cylinder (4) and further swiveling from the first angular position (3A) to a second angular position (ϕ₂) coincides with an increase of the tension of the tensioning device (5).

9. The coupler according to any one of the preceding claims, comprising a stroke limit (43) which limits active swiveling of the coupler (1) by means of the actuating cylinder (4) up to the first angular position (ϕ₁).

10. The coupler according to any one of the preceding claims, wherein the actuating cylinder (4) is activatable in opposite directions so as to enable the actuating cylinder (4) to cause the coupler (1) to swivel about the pivot axis (3A) both from the neutral position to the first angular position (ϕ₁) and from the first angular position (ϕ₁) to the neutral position.

11. The coupler according to any one of the preceding claims, wherein the tensioning device (5) comprises a biasing element (51), preferably a coil spring.

12. The coupler according to any one of the preceding claims, wherein one or both of:

- the first angular position (ϕ₁) is between 20° and 40°, preferably 30°, from the neutral position and

- the second angular position (ϕ₂) is more than 40°, preferably 47°, from the neutral position.

13. The coupler according to any one of the preceding claims, wherein the arrangement is such that swiveling of the coupler (1) about the pivot axis (3A) in a second direction opposite to the first direction between the neutral position and a third angular position (ϕ₃) coincides with an increase of the tension of the tensioning device (5).

14. The coupler according to any one of the preceding claims, wherein
both the tensioning device (5) and the actuating cylinder (4) are located above or below a second, horizontal virtual plane connecting the coupler head (2) and the pivot axis (3A).

15. The coupler according to any one of the preceding claims, comprising a joint (6) between the pivot axis (3A) and the coupler head (2), the joint (6) being configured for enabling the coupler head (2) to be folded backward toward the pivot axis (3A).

16. A car (100) of a multi-car rail vehicle comprising a coupler (1) according to any one of the preceding claims.

17. A method of using the coupler (1) according to any one of claims 1 to 15 on a car (100) of a multi-car rail vehicle, wherein, when the coupler (1) is in an uncoupled state, the coupler (1) is swiveled sideways relative to the car (100) into the first angular position (ϕ₁) using the actuating cylinder (4), wherein preferably the coupler head (2) of the coupler (1) is folded backward toward the pivot axis (3A).

Drawing