AU718858B2

AU718858B2 - Rail vehicle with an articulated joint

Info

Publication number: AU718858B2
Application number: AU70374/98A
Authority: AU
Inventors: Ulrich Hachmann; Andreas Strasser
Original assignee: ABB Daimler Benz Transportation Schweiz AG; ABB Daimler Benz Transportation Technology GmbH
Current assignee: Alstom Transportation Germany GmbH
Priority date: 1997-03-26
Filing date: 1998-03-18
Publication date: 2000-04-20
Anticipated expiration: 2018-03-18
Also published as: CA2284204C; CZ299553B6; CZ9902382A3; ATE207831T1; DE59801962D1; JP2000510414A; HRP980158B1; PL191052B1; CA2284204A1; JP3271989B2; PL334800A1; WO1998042557A3; DE19712752A1; HRP980158A2; DE19712752C2; EP0969997A2; EP0969997B1; AU7037498A; WO1998042557A2

Abstract

The invention relates to a rail vehicle which has two wagon bodies (1, 2) coupled via a single axle articulated joint (8), said wagon bodies each placed elastically on a double axle bogie positioned approximately in the longitudinal central area. Control elements are provided to detect the angle of rotation between the wagon bodies (1, 2) and their corresponding bogies (4), and the angle of articulation at the articulated joint (8) as well as controllable actuators for influencing the angle of articulation depending on the control elements. The angle of articulation is regulated to a control value, said control value being the sum of the current actual angle of articulation measured (K-ist) and the bending angle (A1 and A2), in order to be able to minimise the clearance required whilst the railway vehicle is travelling dynamically.

Description

Rail vehicle with an articulated joint The invention concerns a rail vehicle according to the generic part of the first claim as well as a method to control the angle of articulation for such a rail vehicle.

A known rail vehicle of this type (DE 2854776 Al) is constructed particularly as an articulated tram and comprises two wagon bodies, each of them being supported by a twin-axle bogie arranged approximately along the longitudinal centre of the wagon. At those ends of the two wagon bodies, which face each other, are coupled by means of an articulated joint, the single pivoting axle of which extends vertically. At the same time the pivoting angle between the respective bogie and the associated wagon body is determined by means of a control mechanism with a coupled distance sensor and the angle of articulation is determined by means of at least one distance sensor assigned to the articulated joint. The signals generated by the distance sensor are introduced to a control unit, which controls a servo unit allocated asymmetrically or two servo elements allocated symmetrically to the articulated joint. On this occasion the angle of articulation of the articulated joint is so influenced, that the twin-axle bogie, without a trunnion, on which the wagon bodies are supported via resilient secondary springs, are completely relieved from exercising the function of the force dispenser. In this case, while travelling on a straight section, the servo element blocks the articulated joint in a position over the centre of the track and when travelling in a curve it forces the buckling of the articulated joint to the outside of the curve of the track, thus improving the use of the clearance when the rail vehicle travels on a curve.

The object of the invention is to specify a rail vehicle of the generic type and a method to control same, by which the wagon bodies are controlled during a dynamic travel in a position ,F ,relative each other, which position corresponds to the static Qsition in the actual section of the track.

coupled distance sensor and the angle of articulation is determined by means of at least one distance sensor assigned to the articulated joint. The signals generated by the distance sensor are introduced to the control unit, which controls a servo unit allocated asymmetrically or two servo elements allocated symmetrically to the articulated joint. On this occasion the angle of articulation of the articulated joint is so influenced, that the twin-axle bogie, without a trunnion, on which the wagon bodies are supported via resilient secondary springs, are completely relieved from exercising the function of the force dispenser. In this case, while travelling on a straight section, the servo element blocks the articulated joint in a position over the centre of the track and when travelling in a curve it forces the buckling of the articulated joint to the outside of the curve of the track, thus improving the use of the clearance when the rail vehicle travels on a curve.

The object of the invention is to specify a rail vehicle of the generic type and a method to control same, by which the wagon bodies are controlled during a dynamic travel in a position relative to each other with an improved force introduction, which position corresponds to the static position in the actual section of the track.

According to a first aspect of the invention there is provided a rail vehicle with two wagon bodies which are joined by means of a single-axle articulated joint which can pivot about a vertical axis, each wagon body supported via resilient spring elements on a multi-axle bogie provided in the region of the longitudinal centreline of the wagon body, and with control *o means for the purpose of recording a pivoting angle between the wagon body and the bogie as well as an angle of articulation on the articulated joint i and with controllable servo elements for the purpose of influencing the angle of articulation which is controlled as a function of the control means, in accordance with the relationship Ksoll Kis t a2is t ali t 30 where Kso 0 u the desired value of the angle of articulation, Ki t the actual value of the angle of articulation, ali,;t the actual pivoting angle between the preceding, in the direction of S.travel, bogie and the associated wagon body, and a2is t the actual pivoting angle between the following, in the direction of Itravel, bogie and the associated wagon body, characterised in that additionally or alternatively to the servo elements further servo elements are provided on the articulated joint at least between one of the wagon bodies and the associated bogie and that the further servo elements are controllable damping elements.

According to a second aspect of the invention, there is provided the use of a plurality of rail vehicles, as described above, which are joined to each other by means of a coupling rod each, which on the adjacent wagon bodies has a joint each.

According to a third aspect of the invention, there is provided a method to control the angle of articulation of a rail vehicle, as described above, wherein actual pivoting angles between the bogies and the associated wagon bodies as well as the actual angle of articulation on the articulated joint are measured and that the angle of articulation is controlled by a force acting on the articulated joint, the force being determined in accordance with the sum of the actual angle of articulation, the actual pivoting angle between the following, viewed in the direction of travel, bogie and the wagon body as well as the subtracted actual pivoting angle between the first, viewed in the direction of travel, bogie and the associated wagon body characterised in that from the actually measured pivoting angles, an arithmetic average value is formed and that at least one pivoting angle is controlled towards the arithmetic average value.

In the case of a refinement of a rail vehicle according to the invention on the one hand the actual angle of articulation of the articulated joint and on the other the pivoting angle between the bogies and the associated wagon 25 bodies are determined. The actual values of these angles are added taking their signs into consideration, whereby the pivoting angle between the first bogie, viewed in the direction of travel, and the associated wagon body, is subtracted. The sum of this addition is the measure of the desired angle of articulation which the join should assume under actual operating 9 p which in the case of, for example, a too strong a deflection the following bogie is braked or the preceding wagon is accelerated.

Furthermore, in the case of the servo elements one can deal with active servo elements which not only act against changes when the actual value is drifting away from the desired value, but in the absence of external restoring forces also affect the return of the actual value to the desired value.

When measuring the pivoting angle and the angle of articulation the significance of a sign definition is established, whereby, for example, one will always commence from the value of zero when the longitudinal axes of the respective bogie is parallel to the longitudinal axis of the associated wagon body and the longitudinal axes of the wagon bodies are aligned with each other. The pivoting angles are considered positive when the longitudinal axis of the wagon body is pivoted clockwise relative to the longitudinal axis of the associated bogie. The pivoting angles are considered negative when the longitudinal axis of the wagon body is pivoted anti-clockwise relative to the longitudinal axis of the associated bogie. Negative values of the angle of articulation occur when the preceding wagon body deflects anti-clockwise relative to the following wagon body. Positive values of the angle of articulation occur when the longitudinal axis of the first wagon body deflects clockwise relative to the longitudinal axis of the second wagon body.

A two-element rail vehicle with an articulated joint with a vertical pivoting axis between the two wagon bodies and with resilient restoring elements between the wagon bodies and the respective bogie requires the smallest clearance in the static stationary state. It has been ascertained for this state that when the train is at standstill on any real rail track, the pivoting angles are approximately the same. In the case of a rail vehicle fitted in this manner the control of the pivoting t anqle can be so carried out that first the actual pivoting angles between the bogies and the associated wagon bodies as well as the actual angle of articulation on the articulated joint are measured repeatedly by taking into consideration the positive or negative signs of the angles at least during the travelling. By adding up these angular values an adjusting signal is generated in the control unit, which signal corresponds to the desired value of the angle of articulation and controls the mechanical force components acting against the deviation of the angle of articulation if there is a deviation from the actual angle of articulation measured on the articulation joint. These force components act directly on the articulated joint. Deviations from the ideal angle of articulation, corresponding to the minimum clearance requirement, may arise during operation due to various traction forces on the bogies, in case of unequally working brakes, faulty rails, the spinning of one of the drive wheels, when entering into a curve from a straight section as a result of the acting dynamic force of inertia, in thrust operation or the like.

If two or more similarly controlled two-element trains are joined by means of a coupling rod each, wherein each coupling rod is joined via a joint to the second wagon of the preceding train and to the first wagon of the following train, then all coupled trains are operated according to the same control principle.

It could be of further use to influence at least one of the pivoting angles by means of servo elements for the purpose of minimising the required clearance. At the same time the pivoting angle is controlled towards a desired value, corresponding to the arithmetic average value of the two pivoting angles actually measured during dynamic operation.

The invention is explained in detail based on basic sketches of an embodiment. They show in: Fig.l a two-element rail vehicle with adjusting and control means for the determination of the angles as well as for counteracting, Fig.2 the rail vehicle on a straight section with the longitudinal axes of the wagon bodies being buckled relative to each other, Fig.3 the rail vehicle on a curved rail track.

In the case of a rail vehicle two wagon bodies 1, 2 are provided, each of which being mounted only on a twin-axle bogie 4, without a trunnion, via two resilient secondary spring elements 5, the bogies arranged approximately along the longitudinal centreline of the wagon bodies. The secondary spring elements 5 in turn are arranged on a line extending transversely to the longitudinal axis of the respective wagon body. In addition to their vertical spring properties, the secondary springs 5 allow an additional rotation about a virtual vertical axis and a limited transverse movement. By virtue of this the respective wagon body 1, 2 can carry out a limited rotation in a plane which is parallel to the associated bogie 4 as well as it can carry out a lateral movement. At the same time a movement of the bogie 4 is prevented in the 21. longitudinal direction of the wagon body by virtue of at least S" one connecting rod, which extends in the longitudinal direction and is joined in a pivoting manner to the bogie 4 and the wagon body 1,2, the connecting rod transferring the traction forces between the bogie 4 and the wagon bodies 1 and 2 which occurs in the longitudinal direction of the wagons. Thus the secondary springs 5 make a pivoting of the longitudinal axis of the bogie relative to the longitudinal axis of the associated wagon body feasible by an angle of 'al' and respectively, which, as a rule, may be different for the individual wagons during the operation. For the determination of this angle'a' a pivoting angle sensor 6 each is provided, which is coupled to the Sassociated wagon body 1, 2 on the one hand and to the associated bogie 4 on the other. Depending on the respective pivoting angle the pivoting angle sensors 6 generate the actual pivoting angle signals Vl, V2, which are fed as input signals to a control unit 7.

When the longitudinal axes of the bogie 4 and the associated wagon body 1, 2 are aligned, the pivoting angle sensors 6 generate a value corresponding to 0' of the pivoting angle When the wagon body pivots clockwise relative to the bogie, a signal corresponding to a positive pivoting angle is generated; when the wagon body pivots anti-clockwise relative to the associated bogie, then a signal for a corresponding negative angular value is emitted. The wagon bodies i, 2 are joined to each other by means of a single articulated joint 8, which has a vertical joining axis. An angle of articulation sensor 9 is assigned to the articulated joint, which sensor in the case of the longitudinal axes of the wagon bodies i, 2 lying in one line generates an angle of articulation signal corresponding to an angle of articulation equalling When the longitudinal axis of the wagon body 2 pivots anti-clockwise relative to the longitudinal axis of the wagon body i, the generated angle of articulation signal corresponds to a positive angle of articulation. When, in contrast, the longitudinal axis of the second wagon body pivots clockwise relative to the longitudinal axis of the wagon body i, the generated angle of articulation signal corresponds to a negative angle of articulation. The ,o ~actual signal values generated by the angle of articulation sensor 9, are also fed to the control unit 7 as input signals.

The desired value of the angle of articulation is determined in the control unit 7 by carrying out an addition of the actual pivoting angles 'al' and 'a2' as well as of the actual angle of articulation 'K' according to the equation Kson Kis t a2is t ali t while observing the positive and negative signs of the measured angles. The result of this addition is converted into a control signal, which acts on the articulated joint 8 via servo elements producing mechanical forces. For the purpose of influencing the angle of articulation'K, as servo elements controllable hydraulic actor elements 10 are provided symmetrically about the articulated joint 8 between those ends of the adjacent wagon bodies 1, 2 which face each other, with the aid of which servo elements a force component can be produced between the adjacent wagon bodies i, 2, this component causing an operationally warranted increase or decrease of the angle of articulation 'Kit in accordance with the associated 7 control signal. When, in addition to the angle of articulation at least one of the pivoting angles 'al' and/or 'a2' is controlled, then the arithmetic average value is formed from the two actually measured dynamic pivoting angle values and by means of associated actors 11 the, or both, pivoting angle(s) is (are) controlled on the respective bogie/wagon body by observing the relevant chosen sign definition from this average value. On this occasion it is assumed that the two pivoting angles 'al' and 'a2' are approximately equal when the minimum clearance is required. Each force component produced by the actors 11 acts against the deviation. These actor elements 11 are effectively connected symmetrically to the respective bogie 4 on the one hand and to the associated wagon bodies i, 2 on the other, thus enabling them to carry out a pivoting relative .i each other in accordance with the required angle of articulation. On this occasion the provision of one actor on *e one bogie only may suffice.

Each actor element 10 is equipped with an actor control input AST, which are connected to the corresponding actor control outputs AST1 and AST2 of the control unit 7. The actor elements 11 too have control inputs S, which, in turn, are connected to the corresponding control outputs Si to S4 of the control unit S 7. At the same time the control inputs for the actors 11 of a bogie may be connected parallel to prevent an asymmetrical pivoting of the bogie brought about by these actors 11ii.

The wheels of both sets of wheels of each bogie 4 run in the gauge of a track 13, so that the associated bogie inevitably N assumes a position determined by the rail section being travelled on. This position corresponds essentially to the tangent to the rail section 13 in the region of the respective bogie 4. By virtue of the wagon bodies 1, 2 coupled by the articulated joint 8, in a dynamic travel mode they cannot align freely to correspond with the position of the bogie. Therefore a twisting of the secondary springs 5 about a virtual vertical axis takes place and, as a rule, also a slight transverse movement relative to the longitudinal axes WKL1 and WKL2 of the wagons. This twisting and transverse movement has to be taken up by the respective pairs of secondary springs 5, i.e. the secondary springs 5 store the energy arising from this. in the static state, i.e. when the rail vehicle is stationary and not being braked, the sum of these individual energies is at a minimum. In the travel mode this energy changes due to the additionally acting dynamic forces. Accordingly, in static operation the clearance required for the entire rail vehicle is at a minimum and during travel it reaches values which may exceed the clearance required in the static operation. To enable to counteract this, the control is so carried out that during the dynamic travel the wagon bodies 1, 2 are controlled by means of the actors 10, and possibly 11, into a position corresponding to that of the static state as a function of the actually measured values of the pivoting angle and of the angle of articulation'K'.

In the case of a configuration according to Fig.2 a two-element rail vehicle is situated on a straight section of the track 13.

On this occasion wagon 2 is in the thrust mode, so that the articulated joint 8 and, consequently, the longitudinal axes WKL1 and WKL2 of the wagon bodies are laterally deflected relative to the longitudinal axes DGL1 and DGL2 of the bogies, which axes are in alignment with the section of the track 13.

The pivoting angle sensor 6 on the preceding wagon 1 in this case registers a positive pivoting angle whereas the pivoting angle sensor 6 on the second wagon 2 registers a negative pivoting angle 'a2' of the same magnitude, consequently the longitudinal axis WKL2 of the wagon is pivoted against the longitudinal axis WKL1 of the wagon anti-clockwise relative to the longitudinal axis of the bogie 4. Therefore the actual angle of articulation assumes, by definition, a positive value for the angle of articulation 'KiS', which according to Fig. I corresponds to the sum of the absolute values of the pivotng angles and Thus the angle of articulation is zero in accordance with the conditions of the formula. Therefore the actor, or actors, 10 or 11 have to be so controlled that the angle of articulation is brought to zero, consequently the longitudinal axes WKL1 and WKL2 of the wagons 1 and 2 will be aligned with the longitudinal axes DGL1 and DGL2 of the bogies 4 and thus in the case 1 0 of a straight track 13 are parallel to their longitudinal axes.

If controllable damping elements only are used as actors, then the actors 10 are switched to high damping values already at the commencement of the lateral deflection of the articulated joint 8, thus practically preventing a lateral deviation of the articulated joint. A restoring of the articulated joint is carried out during the operation automatically when, for example, the thrust mode of the wagon 2 finishes or the preceding wagon pulls or is braked to a lesser extent. The restoring forces of the secondary springs 5 assist the reverse pivoting of the longitudinal axes of the wagon bodies into an alignment with the longitudinal axes of the bogies, whereby then damping action of the actors 10 can be appropriately fully cancelled when the actual measured value of the angle of articulation K changes towards the desired value angle of S' articulation. In a corresponding manner, by damping the S pivoting movement, the actors 11 between the bogie 4 and the 30 associated wagon body 1 and/or 2 can counteract a change drifting away from the desired value. When these damping measures are adequate, the control unit 7 can order additionally a braking of the second wagon 2 or an acceleration of the first, preceding, wagon 1 or control the bogies by means of the driving motors. When actors 10 and/or 11, which actively introduce forces, are used, the force components necessary to move the actual value of the angle of articulation to the desired value of the angle of articulation are actively controlled.

When the first wagon 1 pulls on a uniformly curved rail section 13, there is the danger that the actual value of the angle of articulation KI,. will be too small, so that according to Fig.3 the free ends of both wagon bodies 1 and 2 pivot towards the outside the bend and the middle ends of the wagons with the articulated joint 8 pivot towards the inside of the bend thus increasing the clearance required. From the geometrical conditions which, for the purpose of clarification of the operation are exaggerated as far as the geometrical relationships are concerned, it becomes obvious that the angle of articulationi Ki.r is considerably smaller than the desired value K.o 0 which is obtained in the point of intersection of the extended longitudinal axes DGL1 and DGL2 of the bogies 4.

This desired value of the angle of articulation is obtained by considering the lines which are parallel to the longitudinal axes of the bogies according to Fig.3, which pass through the pivoting joint 8, as the sum of the absolute values of the angle of articulationI Kit and of the pivoting angles 'al' and'a2'.

Thus the control unit 7 emits in this case control signals to the actors 10, 11, which will bring an increase of the actually measured angle of articulation about. Provided the increase of 2 the actual value of the angle of articulation is carried out not by deceleration of the preceding wagon 1 or acceleration of the second wagon 2 active force components of the actors have to deflect the articulated joint stronger or the actors 11 have to accomplish a reverse pivoting of the wagon bodies -36 relative to the bogies, or both steps can be controlled see. simultaneously. At the same time care has to be taken that angular values of the magnitude illustrated in Fig.3 cannot occur in practice, since, as a rule, the pivoting angle 'a'is small and the radius of curvature of the rail track is considerably greater than the dimensions of the bogies.

The actual position of the wagon bodies is obtained from the angle of articulation K and the pivoting angles as they are actually measured by the angle of articulation sensor 9 and the pivoting angle sensor 6 and emitted, in particular, as electrical actual value signals K and V and fed to the control unit 7 for further processing. In the control unit the actual value signals are compared with the signals of the desired values of the angle of articulation derived or calculated from them and, as a result of this a control of the actors 10, and possibly of 11, is carried out. At the same time the actors 11 can be so controlled, that in the case of actual value signals lagging behind the desired value, the articulating and/or pivoting forces between the associated wagon bodies and bogie emanating from the vehicle's dynamics, are so assisted that the actual value signals will approach the desired value signals or that when the actual values exceed the desired value they will be controlled in the opposite direction. If, in contrast, the actors are constructed as damping elements only, an active assistance of the pivoting movements to achieve a faster catching up of the actual values with the desired values is not feasible; in this case, however, when the actual value reaches the desired value and afterwards exceeds the desired value, a damping of the movement of the corresponding wagon body is affected. As soon as the actual value starts to approach again the desired value, this damping is cancelled to enable the angle of articulation approach the desired angle of articulation as soon as possible. Should the actual value move towards the desired value too fast and an overshooting is expected, the change of the actual value is slowed down by engaging the damping effect shortly before reaching the desired value.

o The arrangement of the actors 10, 11 has preferably two actor elements each provided symmetrically about the articulated joint 8 and/or the bogies 4. While the actors 11, positioned between the bogie 4 and the wagon body 1 and 2, respectively, S have to operate in the same direction for the purpose of S achieving a symmetrical rotation relative to the associated wagon bodies and therefore for each bogie they can be connected to a common output Sl/S2, S3/S4 of the control unit 7, the actor elements 10 in the region of the respective articulated joint 9 have to be controlled in opposite directions by virtue of their arrangement in a horizontal plane next to the articulated joint. Accordingly, when extending one actor element 10, the other has to be either ineffective or be controlled in the sense of shortening the axial length. When controlling the wagon bodies by influencing the angle of articulation between the longitudinal axes of the wagon bodies, possibly with the aid of controlling the bogies relative to the wagon bodies, the position of the wagon bodies relative each other achieves in the dynamic travel mode an arrangement which approximates very closely the static operation mode. In this case, as far as the actual progress on the rail track is concerned, the rail vehicle requires only an at least approximate ideal clearance and adheres to this especially when faulty operations of the brake and/or drive elements or other influencing factors may lead to a thrusting mode resulting in the deflection of the coupling joint or traction forces may let the angle of articulation become too small when travelling on a curve.

Claims

1. A rail vehicle with two wagon bodies which are joined by means of a single-axle articulated joint which can pivot about a vertical axis, each wagon body supported via resilient spring elements on a multi-axle bogie provided in the region of the longitudinal centreline of the wagon body, and with control means for the purpose of recording a pivoting angle between the wagon and the bogie as well as an angle of articulation on the articulated joint and with controllable servo elements for the purpose of influencing the angle of articulation which is controlled as a function of the control means, in accordance with the relationship Ksoll Kis t a2is t alis t where K,, 1 1 the desired value of the angle of articulation, Kist the actual value of the angle of articulation, alist the actual pivoting angle between the preceding, in the direction of travel, bogie and the associated wagon body, and a2ist the actual pivoting angle between the following, in the direction of travel, bogie and the associated wagon body, characterised in that additionally or alternatively to the servo elements 20 further servo elements are provided on the articulated joint at least between one of the wagon bodies and the associated bogie and that the further servo elements are controllable damping elements.

2. The use of a plurality of rail vehicles according to claim 1, which are joined to each other by means of a coupling rod each, which on the adjacent 25 wagon bodies has a joint each.

3. A method to control the angle of articulation of a rail vehicle according to claim 1, wherein actual pivoting angles between the bogies and the associated wagon bodies as well as the actual angle of articulation on the articulated joint are measured and that the angle of articulation is controlled 30 by a force acting on the articulated joint, the force being determined in accordance with the sum of the actual angle of articulation, the actual pivoting angle between the following, viewed in the direction of travel, bogie and the wagon body as well as the subtracted actual pivoting angle between the first, viewed in the direction of travel, bogie and the associated wagon body characterised in that from the actually measured pivoting angles, an RA ~~T 14 arithmetic average value is formed and that at least one pivoting angle is controlled towards the arithmetic average value.

4. A method according to claim 3, characterised in that the angle of articulation of the articulated joint is changed by means of associated servo elements as a function of the desired value of the angle of articulation.

A method according to claim 4, characterised in that the servo elements are switched to high damping values when the actual value of the angle of articulation moves away from the desired value of the angle of articulation.

6. A rail vehicle substantially as described herein with reference to the accompanying drawings.

7. The use of a plurality of rail vehicles substantially as described herein with reference to the accompanying drawings.

8. A method to control the angle of articulation of a rail vehicle substantially as described herein with reference to the accompanying drawings. :i Dated this twenty-second day of September 1999 a o ABB DAIMLER-BENZ TRANSPORTATION (TECHNOLOGY) i GmbH Patent Attorneys for the Applicant: F B RICE CO VV 0 0 S Sr *.595*p