EP3042821B1 - Bogie with centralized primary suspension - Google Patents

Description

The present invention relates to a railway vehicle bogie, of the type comprising two pairs of wheels, the wheels of a pair being connected to each other by a connecting device to form an axle, said axles being connected to one another. to the other by a frame, each of the axles being hinged to the frame about an axis substantially parallel to the axis of the axles.

The invention also relates to the railway vehicle comprising such a bogie.

Bogies of the aforementioned type are known. The documents US 4,667,603 A , US 4,781,124 A , WO 2013/150694 A1 , EP 2 258 597 A1 (corresponding to the preamble of the product independent claim 1) and EP 2 165 913 A1 describe bogies with primary suspension.

However, such bogies generally comprise four primary suspensions, for suspending the chassis of the truck relative to the axles, and two secondary suspensions, for suspending the vehicle body relative to the bogie frame. The four primary suspensions are each arranged between the axles and the bogie frame at each wheel, which constitutes a complex structure and having a large mass.

Limits on the rolling mass on the rails are introduced to keep the tracks in good condition. One of the current challenges in the field of bogies is thus to lighten the bogies and make them simpler from a structural point of view. A reduction in the mass of the truck makes it possible to carry more goods or people, while limiting the degradation of railways.

An object of the invention is therefore to provide a simpler and lighter bogie.

For this purpose, the subject of the invention is a bogie comprising two main suspension devices, each being connected on the one hand to a different axle, and on the other hand to a single elastic articulation forming a suspension of the chassis with respect to the axles .

The bogie according to the invention thus comprises only one primary suspension, instead of the four traditionally provided. The structure of the bogie is greatly simplified and lightened while maintaining the suspension performance of the bogie.

• l'articulation élastique s'étend sensiblement au droit du centre du bogie ;
• les dispositifs de suspension comprennent chacun une partie extrême en forme de fourche comprenant deux branches fixées au dispositif de liaison de l'essieu correspondant ;
• l'articulation élastique entre les deux dispositifs de suspension est un cylindre en caoutchouc évidé ;
• l'articulation élastique entre les deux dispositifs de suspension comprend un ressort ;
• les dispositifs de liaison comprennent chacun un moteur et un réducteur tel que l'axe du dispositif de liaison est sensiblement parallèle et décalé au moins longitudinalement par rapport à l'axe des roues ;
• l'axe du dispositif de liaison de chaque essieu est plus proche du centre de gravité du bogie que l'axe de la paire de roues correspondante ;
• les essieux comprennent chacun une partie non tournante à laquelle est fixé le dispositif de suspension correspondant à l'essieu ; et
• le bogie comprend deux longerons s'étendant de part et d'autre des essieux, dont chaque dispositif de liaison est articulé à une extrémité de chaque longeron.

According to particular embodiments of the invention, the bogie has one or more of the following characteristics, taken in isolation or according to any combination (s) technically possible (s):

• the elastic articulation extends substantially to the right of the center of the bogie;
• the suspension devices each comprise a fork-shaped end portion comprising two branches fixed to the connecting device of the corresponding axle;
• the elastic articulation between the two suspension devices is a hollow rubber cylinder;
• the elastic articulation between the two suspension devices comprises a spring;
• the connecting devices each comprise a motor and a gear such that the axis of the connecting device is substantially parallel and offset at least longitudinally with respect to the axis of the wheels;
• the axis of the connecting device of each axle is closer to the center of gravity of the bogie than the axis of the corresponding pair of wheels;
• the axles each comprise a non-rotating part to which is fixed the suspension device corresponding to the axle; and
• the bogie comprises two longitudinal members extending on either side of the axles, each connecting device is articulated at one end of each spar.

The invention further relates to a railway vehicle comprising a bogie, as defined above.

• la figure 1 est une vue en perspective du dessus d'un bogie selon l'invention ;
• la figure 2 est une vue en perspective du dessous du bogie représenté sur la figure 1 ;
• la figure 3 est une représentation schématique du bogie vu de dessous ;
• la figure 4 est une représentation schématique de certains éléments du bogie vu de côté, sous une charge voisine de la tare ; et
• la figure 5 est une représentation schématique similaire à la figure 4 lorsqu'une charge supérieure à la tare est appliquée sur le châssis du bogie.

Other features and advantages of the invention will appear on reading the description which follows, given solely by way of example and with reference to the appended drawings, in which:

• the figure 1 is a perspective view from above of a bogie according to the invention;
• the figure 2 is a perspective view of the underside of the bogie shown on the figure 1 ;
• the figure 3 is a schematic representation of the bogie seen from below;
• the figure 4 is a schematic representation of some elements of the bogie seen from the side, under a load close to the tare; and
• the figure 5 is a schematic representation similar to the figure 4 when a load greater than the tare is applied to the bogie frame.

In the description, the terms "vertical" and "horizontal" are defined with respect to a bogie mounted in a railway vehicle and arranged on rails. Thus, a horizontal plane is substantially parallel to the plane in which the axles extend and the vertical plane is substantially parallel to the plane in which the wheels extend. The term "longitudinal" is defined with respect to the direction in which a railway vehicle extends in a horizontal plane and the term "transverse" is defined in a direction substantially perpendicular to the longitudinal direction in a horizontal plane.

With reference to Figures 1 and 2 , a railway vehicle bogie 1 (not shown), for example a subway, a tram or a train, is described. The bogie is intended to be connected in a known manner to a box (not shown) of the railway vehicle.

The bogie 1 comprises two axles 2, 3, a chassis 4, two main suspension devices 6, 7, an elastic articulation 8 and a driving device 10.

Each axle 2, 3 comprises a pair of wheels respectively 12, 13 and 14, 15. In a conventional manner, the wheels may be provided with brake disks 16. The wheels of a pair 12 to 15 are connected to each other. other by a connecting device 18, 20 to form the axle 2, 3.

As schematized at figure 3 each connecting device 18, 20 comprises, on the one hand, a central non-rotating part 26, 28 constituted for example by the casing of a motor 30, 32, or integrating this motor, and on the other hand lateral reduction units 34, 35, 36 and 37. Each gear comprises a small wheel 38 integral in rotation with the motor shaft and a large wheel 39 integral with the axis of a wheel. The small wheel 38 and the large wheel 39 mesh together so that the rotation of the motor shaft causes the wheels 12, 13, 14, 15 to rotate through the gearboxes. The wheels thus rotate about an axis AA 'offset from the axis of rotation of the motor shaft 30, 32 B-B'. The axis of the connecting device 18, 20, substantially coinciding with the axis of rotation of the motor shaft, is here substantially parallel and offset at least longitudinally, and possibly vertically, with respect to the axis of the wheels 12 to 15. The axis of each connecting device 18, 20 is closer to the center of gravity of the bogie 1 than the axis of the pair of wheels 12 to 15 corresponding. The motor 30, 32 is fixed to the chassis of the bogie so as to form a mass suspended relative to the axles and not to suffer the effects of the rail, as will be described later.

With reference to Figures 1 and 2 , the two axles 2, 3 are connected to each other by the chassis 4. The axles 2, 3 are articulated to the chassis 4 about an axis CC 'substantially parallel to the axis of the axles 2, 3, and close to the axis B-B '. The chassis 4 comprises two longitudinal members 40, 42, extending substantially longitudinally. At each of its longitudinal ends, each spar 40, 42 is articulated to one of the connecting devices 18, 20 of the axles 2, 3 about the axis C-C ', by means of articulation 43, 44, 45 and 46. According to one embodiment, the central portion 26, 28, which forms a housing for the motor 30, 32, also forms a cross member of the frame. That is, the central portion 26, 28 extends from one spar to the other substantially transversely and is attached to each of these spars.

Each main suspension device 6, 7 comprises a connecting piece connected by one of its ends 48, 50 to a different axle 2, 3. The end 48, 50 of the connecting piece has for example the shape of a fork comprising two branches 51, 52 fixed to the central portion 26, 28 of the connecting device 18, 20 of the corresponding axle 2, 3. Each branch is for example fixed to a transverse end of the structuring part so as to be able to take up the efforts of each wheel of the truck.

The connecting pieces of the two main suspension devices 6, 7 are fixed to one another at their other end by a single elastic hinge 8. The elastic hinge 8 comprises for example a hollow rubber cylinder secured to the end of one of the connecting pieces and receiving an end integral with the end of the other connecting piece or a spring secured to the end of one of the connecting pieces and constrained against the end of the other connecting piece. The elastic articulation thus forms a ball joint allowing a rotational movement about a longitudinal axis of rotation and a transverse axis of rotation of the end of one of the connecting pieces with respect to the end of the other connecting piece. The elastic articulation 8 extends substantially to the right of the center of the bogie 1, that is to say substantially in the center of the longitudinal members in the longitudinal direction and mid-distance of each of the longitudinal members in the transverse direction. According to the embodiment shown in the figures, the elastic articulation extends vertically above the longitudinal members, that is to say that the longitudinal axis of the joint is offset vertically relative to the longitudinal members.

The drive device 10 is connected at its center to the body of the railway vehicle by a body pivot 56. The drive device 10 also comprises two rods 58, 60 connected by one of their ends to the body pivot 56 and hinged to the body pivot about a substantially vertical axis. Each connecting rod 58, 60 is connected at its other end to a different connecting device 18, 20 and is articulated to this connecting device about a substantially transverse axis. The driving device 10, which has substantially the shape of a Z seen from below, as shown on the Fig. 3 , allows to distribute the movement of the body in the two connecting rods 58, 60 which distribute the forces in the two axles 2, 3. This allows the bogies to rotate independently of the body, so other bogies supporting the body. The train can then take tighter turns than if there were no training devices.

The bogie 1 also comprises two secondary suspensions 70, 72, visible on the figure 1 , arranged on the longitudinal members 40, 42 and on which the rest of the vehicle is intended to rest. These secondary suspensions 70, 72 can dampen the movements of the truck 1 relative to the rest of the vehicle.

On the Figures 4 and 5 , is shown a simplified schematic view of the bogie 1 side to account for the operation of the elastic hinge 8.

To facilitate the explanation, the different fixations are represented by points on the Figures 4 and 5 . The points L and L 'are the connection points of the spar 40 to the connecting devices 18, 20 of the two axles 2, 3. The points F and F' are the fixing points of each main suspension device 6, 7 on the central portion 26, 28 of the corresponding axle 2, 3.

The straight line passing through L (respectively L ') and the center of the wheel 13 (respectively 15) and the straight line passing through F (respectively F') and the center of the wheel form an acute angle α (respectively α ') . α and α 'are here substantially equal.

The two suspension devices 6, 7 meet at the elastic joint 8, here comprising a hollow rubber cylinder.

On the figure 4 , only the tare force is applied on the truck 1.

On the figure 5 , a load greater than the tare (not shown) is applied to the longitudinal members 40. The spar 40 lowers relative to the situation of the figure 4 . The points L and L 'therefore also lower. The spar 40 and the suspension devices 6, 7 being attached to the connecting device 18, 20 of the corresponding axle 2, 3, the moment due to the load applying to the spar 40, and equal to the product of this load and the distance separating the point L to the wheel center, projected horizontally, is taken up by the distance separating the point L to the articulation 8, projected approximately vertically. The angles α and α 'are constant between the situations of the Figures 4 and 5 . The decline of the spar 40 therefore affects the orientation of the suspension devices 6, 7 which tend to come closer. The elastic articulation 8 then serves to control the deflection.

The elastic articulation 8 also allows the truck 1 to resume lane left and ensure the parallelism of the axles while allowing to suspend the frame of the truck 1 and the bogie engines with respect to the axles 2 and 3. The structuring devices 18 and 20 opposite, associated with the two main suspension devices 6 and 7, are connected to each other by the hinge 8 on the one hand and the longitudinal members 40 and 42 by the hinges 43, 44, 45, 46 on the other hand, the assembly thus constituting a frame hinged about a substantially longitudinal axis while maintaining in cooperation with the longitudinal members 40 and 42 the parallelism of the axles 2 and 3.

This invention therefore makes it possible to effectively replace the four primary suspensions in a single suspension, composed of two suspension devices 6, 7 and the elastic articulation 8, thus substantially lightening the bogie.

The bogie has been described as comprising two motors and independent and separate wheel axles each connected to a motor by two reducers. However, it is understood that the invention also applies to bogies comprising only one motor driving in rotation a single axle or not including a motor, in the case of a bogie carrier. The invention also applies to a bogie comprising a shaft connecting the two wheels of an axle and connected to the engine via a single reducer.

Claims (10)

1. Bogie (1) of a railway vehicle, comprising two pairs of wheels (12, 13, 14, 15), the wheels (12, 13, 14, 15) of a pair being connected to one another by a linking device (18, 20) to form an axle (2, 3), said axles (2, 3) being connected to one another by a chassis (4), each of the axles (2, 3) being articulated with the chassis (4) about an axis (C-C') substantially parallel to the axis of the axles (2, 3), characterised in that:
   the bogie (1) comprises two main suspension devices (6, 7), each of which is connected on the one hand to a different axle (2, 3) and on the other hand to a single resilient joint (8) forming a suspension for the chassis (4) relative to the axles (2, 3).
2. Bogie according to claim 1, characterised in that the resilient joint (8) extends substantially in line with the centre of the bogie (1).
3. Bogie according to either claim 1 or claim 2, characterised in that the suspension devices (6, 7) each comprise an end portion (48, 50) in the form of a fork having two branches (51, 52) fixed to the linking device (18, 20) of the corresponding axle (2, 3).
4. Bogie according to any one of the preceding claims, characterised in that the resilient joint (8) between the two suspension devices (6, 7) is a hollow rubber cylinder.
5. Bogie according to any one of claims 1 to 3, characterised in that the resilient joint (8) between the two suspension devices (6, 7) comprises a spring.
6. Bogie according to any one of the preceding claims, characterised in that the linking devices (18, 20) each comprise a motor (30, 32) and a reducer (35, 36, 37, 39), such that the axis of the linking device (18, 20) is substantially parallel to and offset, at least longitudinally, relative to the axis of the wheels (A-A').
7. Bogie according to claim 6, characterised in that the axis of the linking device (18, 20) of each axle (2, 3) is closer to the centre of gravity of the bogie (1) than the axis of the corresponding pair of wheels (A-A').
8. Bogie according to any one of the preceding claims, characterised in that the axles (2, 3) each comprise a non-rotating part (26, 28) to which the suspension device (6, 7) corresponding to the axle (2, 3) is fixed.
9. Bogie according to any one of the preceding claims, characterised in that the bogie (1) comprises two side members (40, 42) extending on either side of the axles (2, 3), each linking device (18, 20) of the axles being articulated with one end of each longitudinal member (40, 42).
10. Railway vehicle comprising at least one bogie (1) according to any one of claims 1 to 9.

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