EP2585351B1

EP2585351B1 - A buckling-resistant coupling arrangement for rail vehicles

Info

Publication number: EP2585351B1
Application number: EP11798444.3A
Authority: EP
Inventors: Anders Svedbo
Original assignee: EGO INTERNATIONAL BV
Current assignee: Dellner Couplers AB
Priority date: 2010-06-23
Filing date: 2011-06-08
Publication date: 2018-12-26
Anticipated expiration: 2031-06-08
Also published as: ES2717636T3; PL2585351T3; EP2585351A1; SE1050675A1; SE534924C2; EP2585351A4; WO2011162672A1

Description

TECHNICAL FIELD OF THE INVENTION

The present invention concerns a coupling arrangement for rail vehicles, and more precisely a coupling arrangement of the type that comprises a drawbar and a coupler head, which in a rear end is attached to the drawbar and extends in the longitudinal direction of the same to a front end that is arranged to carry a front plate having a guide cone projecting from the surface thereof, which coupler head furthermore houses components of a mechanical coupling effective for automatic coupling to the corresponding coupling components in an opposite coupler head of a connecting coupling arrangement.

BACKGROUND AND PRIOR ART

A danger in a collision between rail vehicles is that the coupling arrangements that couple together the rail vehicles are separated, which increases the risk of derailment and the risk of the vehicles climbing up on each other.
With the purpose of reducing this risk, different measures are previously known to at least within a limited force range guarantee that the coupling arrangements remain in engaging position after a collision. Known solutions comprise, for example, shock-absorbing elastic damping devices introduced in the coupling arrangement, but also devices that are arranged to be plastically deformed in the event of a collision, in the conversion of at least a portion of the generated force into kinetic energy and heat. To these latter devices, expanding or compressible deformation tubes typically belong, which may be included in the fixing of the coupling arrangement in a car chassis, or which may be integrated parts of the drawbar. As an example of the latter, EP 1 312 527 A1 or EP 1 663 755 B1 could be pointed out.
The coupler head of an automatic coupler, which in a surrounding housing accommodates the mechanical coupling components necessary for coupling for automatic coupling to a connecting coupler, is usually made of castings and lacks typically shock-absorbing ability. A coupler head housing made of weldable forged steel for a central buffer coupling is, however, previously known from DE 1 124 535 . This coupler head housing is dimensioned for resisting occurring normal traction and thrust forces, but lacks measures for a predetermined shock-absorbing deformation in the event of a collision.
Another example of a coupling arrangement for a railway vehicle is known from document DE 20 2007 001773 U1 .

BRIEF DESCRIPTION OF THE INVENTION

The invention aims at generally increasing the capability of a coupling arrangement of absorbing deforming compressive forces and thereby providing an increased protection against deformation of the car chassis.
An object of the invention is to provide a coupling arrangement for the automatic coupling of rail vehicles, which coupling arrangement is arranged to be deformed in a predetermined way while absorbing energy.
Another object of the invention is to provide a coupling arrangement that, by a predetermined deformation, is arranged to prevent a separation between coupled coupling arrangements, and particularly a coupling arrangement that, by a predetermined deformation, is arranged to create a locking between the intercoupled coupling arrangements.
In brief, a coupling arrangement is provided of the type indicated by way of introduction in which, as an extension of the drawbar, an element extends forward through the coupler head toward the guide cone, in addition to which the coupler head, upon application of a deforming compressive force, is arranged to be subjected to an axial compression and/or a rectilinear motion and displacement rearward on the drawbar while carrying along the front plate, with the result that said element is brought into a thrust force-transmitting relationship to the guide cone and is caused to penetrate the front plate.
The technical effect of this solution is that the coupler heads are mutually locked in a thrust force-transmitting engagement. The mutually overlapping elements in the extension of the drawbar provide a bending- or buckling-resistant connection in respect of radial directions, whereby a lateral and vertical, respectively, separation of the couplers is counteracted.
The technical effect is furthermore that the penetration of the element through the front plate takes place via the opening situated right in front of the guide cone and going through the front plate, which acts as a guiding of the motion of the element into the opposite coupler head.
It is in addition preferred that the element has the requisite axial stiffness for, at a deforming collision, knocking the guide cone out of its attachment in the front plate.
By the guide cone in this way being carried along by the element upon the penetration into the opposite coupler head, a part of the force arising at the collision is dissipated. The embodiment also implies a distribution of the force over a larger surface upon the retardation of the knocked-out guide cone against the inside of the coupler head, which reduces the risk of the wall of the coupler head housing bursting, and instead being deformed, in particular expanded, in a way that is favourable for the absorption of energy.
The element in the extension of the drawbar may advantageously consist of a separate, thrust force-transmitting element, which is arranged between the drawbar and the guide cone. In this embodiment, the coupler head housing is shaped in such a way that the thrust force-transmitting element can extend freely past the components included in the mechanical coupling, either beside these, or above and under, respectively, the same.
A preferred embodiment involves that the element in the extension of the drawbar extends in traction force-transmitting engagement with the coupling. In addition, the coupling may be displaceably supported in the longitudinal direction of an elongate groove arranged in the element. In these embodiments, the element extends essentially in the longitudinal direction of the drawbar up to the coupling, so as to from here deflect at an angle to the guide cone.
In particular, it is preferred that the element in the extension of the drawbar has a side surface angled to the longitudinal direction and intersecting the axial centre line of the coupling arrangement, which surface is arranged and effective for the guiding of the corresponding surface of the thrust force-transmitting element of the opposite coupler head upon the elements' mutual displacement and penetration into the respective coupler head.
In a preferred embodiment of the invention, the predetermined deformation of the coupler head comprises one or more notches made in the coupler head housing for the axial compression of the coupler head housing, in particular one or more notches for the folding of the coupler head housing.
In another preferred embodiment of the invention, the coupler head is connected with the drawbar by means of a collar surrounding the drawbar in front of a shoulder formed on the same, and is displaceable on the drawbar in the longitudinal direction against the force of a radial expansion of said collar caused by the shoulder.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be elucidated below by embodiment examples and reference being made to the accompanying schematic drawings, of which

Fig. 1 shows a partially broken-away view from above of a coupling arrangement according to the invention;
Fig. 2 shows the coupling arrangement in Fig. 1 in deformed state after collision;
Fig. 3 shows the coupling arrangement in Fig. 1 in a partially sectioned side view, and
Fig. 4 shows an alternative embodiment of a thrust force-transmitting element included in the coupling arrangement.

DETAILED DESCRIPTION OF EMBODIMENT EXAMPLES

It should be appreciated that the drawing figures are schematic and only suited to elucidate the general idea of the invention such as the same is seen in the written description and in the connecting claims. Therefore, the invention should not be considered limited to shown dimensions, geometries or to the embodiment of design details in the embodiment examples, because these have to be considered by a person skilled in the art in each individual application of the invention. In particular, it should be noted that material thicknesses and other dimensions may be over dimensioned and the constructive design of details simplified, for reasons of drawing technique.
The drawing figures schematically show a coupling arrangement comprising a drawbar 1, which in its inner end is mountable in a car chassis and in its outer end carries a coupler head 2. The coupler head 2 comprises a coupler head housing 3 and is, in a first and rear end, attachable to the drawbar 1, and in a second and front end arranged for carrying a front plate 4, typically comprising a guide cone 5 for the alignment of the coupler heads upon coupling to a connecting coupling arrangement. The guide cone 5 may consist of a separate element mounted to the front plate 4, but may alternatively be integratedly formed as a part of a cast or compression-moulded front plate. Components included in a mechanical coupling 6, such as a central plate 7 and a coupling link 8, are housed in the coupler head housing and rotatably carried on a pivot or shaft 9, which in turn is supported in the coupler head housing (see reference numeral 10). Devices for the locking/unlocking of the coupling mechanism are for the sake of simplicity excluded from the drawing figures, as well as devices for the connection of electricity and pneumatics/hydraulics, which usually are carried on the outside of the coupler head.
The coupler head housing 3 has a box-shaped structure and consists of an upper part 11 (see in particular Fig. 3 ), a bottom 12, and two opposite sides 13 and 14, respectively. The upper part and the bottom, as well as the two sides, may be mutually identically shaped with the exception of externally or internally arranged attachments and seats for the mounting of additional equipment.
As is seen in the drawing figures, the coupler head housing is generally shaped as a funnel the sides of which may be bent in such a way that a predetermined folding and axial compression of the coupler head housing is provided as a result of a deforming compressive force acting in the longitudinal direction of the coupling arrangement.
In the connection area between the coupler head and the drawbar, the coupler head has, in its rear end, a collar 15, which surrounds the drawbar in front of a shoulder 16 arranged on the drawbar. The shoulder 16 protrudes radially from the drawbar and has an oblique front surface 17 facing the collar. The front surface 17 forms a conical ring over which the collar 15 is forced to expand radially in the event of the rectilinear displacement of the coupler head rearward on the drawbar in the direction FB, the front plate 4 being carried along toward the drawbar. A stop (not shown) fixedly arranged on the drawbar may be arranged behind the shoulder 17 so as to limit the possible length of the rectilinear motion. Alternatively, as is illustrated in the drawings, the displacement of the coupler head inward on the drawbar may be limited by the collar being stopped against a flange coupling 18 by which the coupling arrangement is mountable in a car chassis. The reference numeral 19 in Fig. 1 designates a seat formed in the drawbar for the receipt of a shear pin (not shown), which, where appropriate, has the purpose of guaranteeing the axial fixation of the coupler head on the drawbar in normal operating conditions.
The coupler head is preferably made from steel, the elasticity and ability of the steel to be plastically deformed when subjected to loads above its yield point being utilized to convert a deforming compressive force into kinetic energy and heat. In particular, it is taught that at least said collar, and preferably the coupler head housing in its entirety, is made from a high-strength steel, such as an advanced high-strength steel or a steel having extra high or ultra high strength, whereby the required strength to resist normal traction or thrusts occurring during operation can be provided also in a coupler head of reduced weight.
A construction element 20 extends through the coupler head in the extension of the drawbar, essentially up to the back side of the front plate 4. A front part of the element 20 runs in a direction that deviates from the longitudinal direction of the coupling arrangement, and more precisely toward the guide cone 5 carried in the front plate. The element 20 may have such a length that the same with its front end extends up to abutment against support surfaces of the guide cone 5 formed for the purpose, in the way that schematically is illustrated in Fig. 3, but may alternatively terminate a short distance behind the guide cone. However, the element 20 should at least be of such a length that it, as a result of the motion of the front plate caused by the rectilinear motion of the coupler head rearward on the drawbar and/or by the compression of the coupler head housing, generates a thrust force-transmitting action and, as a result thereof, penetrates the front plate 4 and a distance into the opposite coupler head, as is illustrated in Fig. 2. In this position, the elements 20 inserted into the respective coupler head cause a mutual engagement between the coupling arrangements in the direction of the thrust force and in this way counteracts mutual movement between the coupling arrangements in radial directions, i.e., laterally and vertically.
The element 20 may, as is shown in the embodiment example in Figs. 1-3, consist of a fork-shaped element that is connected with the drawbar 1 or integrated in the same and primarily extends in the longitudinal direction of the drawbar past the coupling 6, in order to deflect, in the area of the same, at an angle from the longitudinal axis and toward the guide cone 5. In this embodiment, the shaft 9 included in the coupling 6 extends through the element 20, and may via the element 20 be in traction force-transmitting connection with the drawbar.
In the embodiment example in Figs. 1-3, the element 20 consists of an upper part 20' running in the gap between the coupling 6 and the upper part 11 of the coupler head housing, and a corresponding lower part 20" that runs in the gap between the coupling 6 and the bottom 12 of the coupler head housing. In this embodiment, the two parts 20' and 20" of the element form a respective guiding of the upper part and bottom of the coupler head housing in the course of the deformation of the coupler head housing. The side 21 of the element 20 situated closer to the centre of the coupling arrangement is oblique at an angle intersecting the centre line, and forms a guiding surface 21, against which the corresponding side surface of the thrust force-transmitting element 20 of the meeting coupler head slides in the course of deformation.
As is shown in Fig. 4, the element may alternatively consist of a separate thrust force-transmitting element 22, which in a rear end rests against the drawbar 1, and which in a front end rests against the inside of the guide cone 5. The element 22 may, for example, be made as a rod, a beam, a sturdy sheet-metal plate or a clamp, and is, like the element 20, made with the requisite axial stiffness to deform the front plate and penetrate into the opposite coupler head in the event of a collision. Both in the case of an element 20 connected or integrated with the drawbar and in the case of a separate element 22, the same may advantageously consist of an element manufactured from compression-moulded steel, which by expedient shape can be furnished the requisite axial stiffness also in a comparatively light structure.
In a collision, which triggers the compression and/or rectilinear motion of the coupler head on the drawbar 1, the thrust force-transmitting element 20, 22 causes the guide cone 5 to be knocked off from its fixing in the front plate, and carried along by the element into the opposite coupler head such as schematically is illustrated in Fig. 2. Notwithstanding whether the guide cone 5 is welded or bolted to the front plate, or is a part integrated with the front plate, the guide cone or the connection area thereof in the front plate may be made with notches, such as indications of fracture or weakenings in the material or connection members, which allows knocking out with an essentially maintained integrity of the guide cone 5.
It will be appreciated by a person skilled in the art that a complete quenching or absorption of energy that is generated, for instance, in a collision only can be expected in connection with forces up to a certain magnitude, while forces exceeding this magnitude result in a no longer predictable deformation. The primary object of the invention is, however, still achieved, because the energy that is dissipated during the predetermined deformation of the coupler head implies a corresponding reduction of the initial force. In combination with other shock-absorbing devices, known per se, in the coupler, the invention implies that more energy can be absorbed before the car chassis is affected by a deforming force.
At forces up to a magnitude that can be absorbed by a predetermined and controlled deformation according to what is taught in the invention, the specific object of the invention is also achieved by a coupling arrangement that is arranged with a thrust force-transmitting element that, at the deformation of the coupler head, guarantees a buckling-resistant connection between intercoupled coupling arrangements.

Claims

Coupling arrangement for a railway vehicle comprising a drawbar (1) and a coupler head (2), which in a rear end is attached to the drawbar and extends in the longitudinal direction of the same to a front end that is arranged to carry a front plate (4) having a guide cone (5) projecting from the surface thereof, which coupler head furthermore houses components (7-10) of a mechanical coupling (6) effective for automatic coupling to the corresponding coupling components in an opposite coupler head of a connecting coupling arrangement, characterized in that, as an extension of the drawbar, an element (20, 22) extends forward through the coupler head toward the guide cone (5), as well as in that, upon application of a deforming compressive force, the coupler head (2) is arranged to be subjected to an axial compression and/or a displacement rearward on the drawbar while carrying along the front plate (4) with the result that said element (20, 22) is brought into a thrust force-transmitting relationship to the guide cone (5) and is caused to penetrate the front plate.
Coupling arrangement for a railway vehicle according to claim 1, wherein the element (20, 22) has axial stiffness for, in a collision, knocking the guide cone (5) out of its attachment in the front plate (4).
Coupling arrangement for a railway vehicle according to claim 1 or claim 2, wherein the element (22) consists of a separate thrust force-transmitting element arranged between the drawbar (1) and the guide cone (5).
Coupling arrangement for a railway vehicle according to any one of claims 1-3, wherein the element (20) is in traction force-transmitting engagement with the coupling (6).
Coupling arrangement for a railway vehicle according to claim 4, wherein the coupling (6) is displaceably supported in the longitudinal direction in an elongate groove arranged in the element (20).
Coupling arrangement for a railway vehicle according to claim 4 or 5, wherein the element (20) has a side surface (21) angled to the longitudinal direction and intersecting the axial centre line of the coupling arrangement, which surface is effective for the guiding of the corresponding surface of the thrust force-transmitting element (20) of the opposite coupler head.
Coupling arrangement for a railway vehicle according to any one of the preceding claims, wherein the coupler head comprises notch for the axial compression of the coupler head housing, in particular notch for the folding of the coupler head housing.
Coupling arrangement for a railway vehicle according to any one of the preceding claims, wherein the coupler head is connected with the drawbar by means of a collar (15) surrounding the drawbar in front of a shoulder (16) formed on the same, and is displaceable on the drawbar in the longitudinal direction against the force of a radial expansion of said collar caused by the shoulder.