GB2165808A

GB2165808A - Railway bogie having a bearing to allow vehicle tilt and swivel motions

Info

Publication number: GB2165808A
Application number: GB08525863A
Authority: GB
Inventors: Alessandro Marzocco
Original assignee: Socimi; Societa Costruzioni Industriali Milano SpA SOCIMI
Current assignee: Socimi; Societa Costruzioni Industriali Milano SpA SOCIMI
Priority date: 1984-10-22
Filing date: 1985-10-21
Publication date: 1986-04-23
Also published as: BR8505271A; GB2165808B; NL8502866A; NO165388B; IT8423268A0; SE462275B; ZA851016B; GR852552B; FI854093L; FI854093A0; PT81353B; NO165388C; NO854197L; IE852595L; LU86131A1; FI85249C; CA1275860C; GB8525863D0; FI85249B; FR2572041A1

Abstract

The bearing is so shaped as to allow the vehicle to tilt relatively to the bogie both around a vertical axis 20 and a horizontal axis. The bearing is semi-spherical and is supported by a transverse beam 3 of the bogie, which is in turn supported by the frame 4 of the bogie, with the interposition of springs (6). The footstep bearing can alternatively be supported by the frame of the bogie and support the tilting beam, which in its turn is linked to the body with the interposition of springs. <IMAGE>

Description

SPECIFICATION Railway bogie for railway vehicles of the tilting body type The present invention relates to a railway bogie for railway vehicles of the tilting body type.

It is known that the railroads, in curve, show a certain degree of superelevation of the track, to the purpose of reducing the effect of the centrifugal acceleration to which the vehicles are subject.

Such a superelevation allows the curves to be faced at higher speeds.

For stability reasons, the superelevation values are limited by international regulations.

To the purpose of further increasing the speed of the vehicles in the curves, without submitting the passengers to unacceptable values of the centrifugal acceleration, the principle is known of rendering variable the position of the body of the railway vehicle, by suitably tilting the same relatively to the bogies towards the inside of the curve, by means of suitable mechanical devices. In this way, to the track superelevation angle, the angle is added of body tilting, compensating in the curve totally or partly on the passengers the greater accelerations produced by the higher speed.

The systems known suffer however from the drawback that they do not allow bodies to be used of traditional structure for tilting body vehicles, and hence require special bogies and bodies to be built.

The object of the present invention is a structure for a railway bogie, either driving or idler bogie, to be used in passenger cars and also in locomotives, suitable to suitably tilt the body of the vehicle in relation to the curvature radius of the track, at the highest reachable speed,as well as to the general conditions of track equipment, said structure being such as to be capable of using, without structural changes, the existing vehicle bodies, or new bodies of traditional design, by replacing the existing bogies with those according to the invention.

To this purpose, a railway bogie is provided according to the invention, for tilting body railway vehicles, comprising a frame with a tilting transverse beam for supporting the body of the railway vehicle with the possibility of rotation around a vertical axis and an horizontal axis, characterized in that it has a footstep bearing so shaped as to allow both the tilting of the body around said vertical axis, and the tilting of the body around said horizontal axis.

A bogie according to the invention offers therefore, relatively to the already known existing bogies, many advantages, such as e.g.: the structural simpleness, the quickness of existing vehicles transformation, in that it does not require long times and great investments for new vehicles, and consequently: strong reduction of the starting investment, and of the availability delays of the tilting body vehicles to be put into service.

The bogie, which is the object of the present invention, can have e.g. its frame of the welded type, consisting of two side members, and of one or more transverse beams, they too being welded.

That notwithstanding, such elements of the structure of the frame could be cast as well, instead of being welded.

The bogie can be provided with primary and secondary suspensions, which may be of any presently used types, and are not bound to the specific structure which realizes the variable position of tilting body relatively to the bogies according to the present invention.

The bogie can be provided with a tilting transverse beam positioned on the upper side, or on the lower side relatively to the springs of the secondary suspension.

The bogie may be integrated by side suspensions of the pneumatic cylinder type, or of the pneumatic-hydraulic cylinder type, whose function is of keeping the centre of the footstep bearing at the centre of the frame of the bogie during the running in the curve, equilibrating the centrifugal force. The tilting of the body takes place around an axis lying on the longitudinal symmetry plane. In this way, the tilting of the body is obtained, which produced the partial or total compensation of the centrifugal acceleration in curve.

Further details of the invention will be clearer from the following disclosure, which relates to some exemplifying embodiments of the invention, shown in the drawings, in which: Figure 1 is a transversal view, partly in section, of a bogie according to the invention; Figure 2 is a view similar to that of Figure 1, but with a different suspension system; Figures 3 and 4 are transversal views, partly in section, of another practical embodiment of the invention, with two different suspension systems; Figure 5 is a top view of a bogie according to the invention; Figure 6 shows a further practical embodiment of a bogie, in a partly in section transversal view.

The spherical footstep bearing 1 allows the rota- tion of the tilting beam 3 and of the frame of the bogie 4 in all directions relatively to the body 2, i.e., both around a vertical axis and around a horizontal axis. The spherical footstep bearing 1 is provided with the vertical safety pivot 20 and with two pairs of facing supports 21 and 22 (Figure 5). The elements 21 are solid with the upper component of the footstep bearing, the elements 22 with the lower component of the footstep bearing. The purpose of said supports is of suitably limiting the tilting angle of the footstep bearing 1 in the longitudinal vertical plane.

The present invention has all the notable advantages described above, consequent to the simpleness of the system, owing to the fact that the characteristic described above of the spherical footstep bearing is also used to the purpose of obtaining the angular movement of the body, by varying its position relatively to the tilting beam 3 and to the frame of the bogie 4 in the transversal vertical plane, as shown by dotted lines.

As it can be seen in Figures 1 and 2, the footstep bearing comprises a substantially semisphericai hollow part, movable between two conjugated parts held together and respectively fastened to the oscillating transverse beam 3 and to the body 2. The hollow semispherical part has such an opening, as to allow it to rotate relatively to the conjugated parts also around a horizontal axis.

The drive of the tilting of the body 2 relatively to the oscillating transverse beam 3 in function of the centrifugal force F is carried out by means of hydraulic cylinders 5 of simple type, or of telescopic type. The cylinders 5 are protected by suitable protecting covers 17.

The basis of each cylinder 5 is fastened inside a suitable cavity provided in the oscillating beam 3, whilst the upper end of the relevant piston is housed and leant, with the interposition of a thrust bearing of the ball bearing type or of another type, inside a corresponding cavity provided in the body, so as to reduce the space occupied by them.

Cylinders 15 of pneumatic type or of pneumatichydraulic type are additionally foreseen, for the drive of the lateral active suspension; they are installed between the oscillating transverse beam 3 and the side members 4 of the frame of the bogie and their pistons are protected by protecting covers 17'.

Stop pads 16 positioned between the oscillating transverse beam 3 and the body 2 have the function of mechanically limiting the rotation of the body 2 relatively to the oscillating transverse beam 3 to the maximum allowable limit, at the same time avoiding possible dangerous impact stresses on the cylinders 5.

Said stop pads 16 are provided with antifriction contact surfaces for a rigid or elasticized contact, as well as with a device for the adjustment, after the assembling, in a precise way, of the maximum value of the rotation angle of the body in its tilting condition.

The stop pads 16 can be of fixed type, or of movable type. The stop pads of the movable type are in their resting condition during the normal operating of the tilting system, thus acting, in that sense, only as stroke end pads. Under their operating condition, they extend out of their seat, being hydraulically andlor mechanically actuated, going along a same stroke, to the purpose of acting as a safety device, which brings back the body 2 to its vertical position, and blocks it in said position, should the tilting system be excluded. The movable pads 16 can also be used as emergency device, totally replacing the drive cylinders 5, for actuating the tilting positioning.

Figures 1 and 2 differ to each other only in that in Figure 1 the secondary suspension of the bogie is realized by means of pneumatic springs 6, whilst in Figure 2 it is realized by means of traditional steel helical springs 6'. In both cases, the secondary suspension is integrated by lateral 18 and vertical 19 side hydraulic dampeners, positioned between the transverse beam 3 and the side members 4 of the frame of the bogie.

In practical embodiment shown in Figures 3 and 4, the function of rotating the bogie relatively to the body in the horizontal plane is effected by the lower cylindrical footstep bearing 7, whilst the function of rotating the body 2 in the transversal vertical plane is effected only by the upper footstep bearing 8 of cylindrical sector shape. The front and rear ends, in longitudinal sense, of the intermediate element 9 of the footstep bearing are formed by vertical walls suitable to bear the longitudinal pushes which are shown between the body 2 and the bogie 3-4.

Basically, the footstep bearing comprises in this case an intermediate part 9 linked with a cylindrical geometrical coupling to the footstep bearing parts respectively fixed to the body and to the frame, the axes of the cylindrical parts being orthogonal to each other. The parts are assembled together by the vertical pivot 20.

In Figure 5 a type of bogie is shown, for exemplifying purposes, in its basic components, having a structure according to the invention.

The bogie is formed by the axles 10, by the disc brakes 11, by the brake cylinders 12, while the frame of the bogie is formed by: end transverse beams 13, intermediate transverse beams 14, side members 4, as well as by the oscillating transverse beam 3, drive hydraulic cylinders 5 and spherical footstep bearing, e.g. of the type shown in Figures 1 and 2.

In Figure 6 the transversal section is shown, for exemplifying purposes, of another possible type of bogie according to the invention. This allows the advantageous characteristics according to the invention to be evidenced, which, always thanks to its characteristics of structural simpleness, can be used in a simple way on any types of bogie provided with the tilting transverse beam 3, transforming the bogie from a normal type bogie to a bogie of the type for tilting body systems The bogie shown in Figure 6 differs from that shown in Figures 1-5, in that the tilting transverse beam 3 is mounted beneath the springs 6 of the pneumatic type shown in the Figure, or of the cylindrical helical spring type.

In this Figure, the body 2 is supported by the tilting transverse beam 3 by the interposition of the springs 6, and the same transverse beam 3 leans on the frame of the bogie 4 with the interposition of the footstep bearing of compound type 7, 8, 9 as shown in Figure 3 or 4, or with the interposition of the footstep bearing of type 1 shown in Figures 1 or 2.

The tilting of the frame 4 of the bogie in curve, in the horizontal plane, takes place relatively to the tilting transverse beam 3 and hence relatively to the body 2, as these latter do not rotate relatively to each other in curve in this plane.

The tilting of the body 2 and of the tilting transverse 3 in the transversal vertical plane takes place always by means of the footstep bearing of compound type 7, 8, 9 or by means of the footstep bearing of simple type 1, relatively to the frame of the bogie 4.

The drive hydraulic cylinders 5 confer to the tilting transverse beam 3 and hence to the body 2 the angular transversal tilting positioning motion.

The basis of the cylinders 5 is fastened e.g. inside the side members 4, while the upper end of relevant pistons is leant inside a cavity provided inside the transverse beam 3 with the interposition of a thrust bearing of the ball bearing type, or of another type. The bearing is used to the purpose of making slide freely the upper end of the relevant piston relatively to the transverse beam 3 during the sliding movement which takes place when the frame 4 of the bogie rotates when entering a curve.

The bogie shown in Figure 6 is equipped with all the fundamental elements typical for a railway bogie, already shown in Figure 5.

As it can be easily seen from what disclosed, a railway bogie of the tilting type, provided with the system according to the invention, is suitable to allow, during the running in a curve, with complete safety, higher speeds than those which can be obtained with the traditional bogies, partly or totally compensating the effect of the centrifugal acceleration on the passengers.

Moreover, with a bogie according to the invention, the structure of the body may remain the traditional structure, so that a bogie according to the invention is also suitable to be applied to already existing railway vehicles, as a replacement for the traditional bogies, with notable economic advantages.

The bogie disclosed, in addition to performing all the existing functions between the body and the bogie, i.e., of rotation in all planes and in all directions, included the rotation of the body in the vertical transversal plane for obtaining the tilting positioning action, performs also the function of transmitting all dynamic and static forces produced by the weights, and all the horizontal dynamic, longitudinal and transversal forces produced by the traction, by the braking and by the centrifugal force.

Claims

1. Railway bogie for railway vehicles of the tilting body type, comprising a frame with a tilting transverse beam for supporting the body of the railway vehicle, with the possibility of rotating around a vertical axis and a horizontal axis, characterized in that it has a footstep bearing so shaped, as to allow both the rotation of the body around said vertical axis, and the rotation of the body around said horizontal axis.

2. Railway bogie according to claim 1, characterized in that said footstep bearing comprises a substantially semispherical hollow part, movable between conjugated parts kept together and fastened respectively to the tilting transverse beam and to the body, said semispherical hollow part being provided with an opening for the passage through it of linking means of said conjugated parts, the opening having such dimensions as to allow said semispherical hollow part to rotate relatively to said conjugated parts around said axes.

3. Railway bogie according to claim 1, characterized in that said footstep bearing comprises an intermediate part coupled with cylindrical geometric coupling with relating footstep bearing parts fastened respectively to the frame and to the body, the axes of the cylindrical parts being orthogonal to each other and said parts being all kept together by connecting means, suitable to allow said parts to rotate around said axes.

4. Railway bogie according to one of claims 2 or 3, characterized in that said connecting means are formed by a safety pivot extending substantially vertically.

5. Railway bogie according to one or more of preceding claims, characterized in that for the movement of the body relatively to the tilting transverse beam in the vertical transversal plane around said horizontal axis hydraulic, simple or telescopic cylinders are provided, positioned between the tilting transverse beam and the body, said cylinders being preferably housed within related cavities of the transverse beam and of the body.

6. Railway bogie according to claim 5, characterized in that the pistons of said hydraulic c-,' ders are provided with related thrust ball bearings in oil bath or similar low friction bearings, suitable to avoid horizontal stresses on the related cylinders during the rotation of the bogie relatively to the body.

7. Railway bogie according to one or more of preceding claims, characterized in that the oscillating transverse beam is provided, in correspondence of its ends, with stop pads, preferably adjustable in height, suitable to cooperate with related pads positioned on the body, the contact surfaces being of rigid type or of elasticized type, made of anti-friction material.

8. Railway bogie according to one or more of claims from 1 to 6, characterized in that the oscillating transverse beam is provided, in correspondence of its ends, with stop pads movable in function of the inclination angle in the transversal plane of the body relatively to the oscillating transverse beam.

9. Railway bogie according to one or more or the claims from 1 to 6, characterized in that the oscillating transverse beam is provided, in correspondence of its ends, with stop pads movable in opposite directions and suitable to cooperate with the body for forming a safety device which brings back the body to its vertical position.

10. Railway bogie according to one or more of preceding claims, characterized in that it supports one or more motor(s).

11. Railway bogie according to one or more preceding claims, characterized in that the oscillating transverse beam supports the body, with the interposition of springs, and that the footstep bearing is positioned between the oscillating transverse beam and a fixed transverse beam of the bogie frame.