CA1077781A

CA1077781A - Railway vehicle

Info

Publication number: CA1077781A
Application number: CA266,752A
Authority: CA
Inventors: Bengt-Goran Ericson; Henry Halldin; Lage Marcusson
Original assignee: ASEA AB
Current assignee: ABB Norden Holding AB
Priority date: 1975-12-01
Filing date: 1976-11-29
Publication date: 1980-05-20
Also published as: DK538576A; SE7513473L; SE395415B; NO764067L; NO140818C; NO140818B; DK141198C; DK141198B

Abstract

ABSTRACT OF THE DISCLOSURE
A railway vehicle has bogies and a body movably suspended thereon. In the interest of passenger comfort and to amend the guard against a tendency of the vehicle to over-turn outwardly in a curve, the vehicle is provided with a suspension mechanism for rolling the body into a suitably angular position in relation to the bogies. The rolling is guided by swinging arms arranged in a certain angular position.
By rolling the body, the center of gravity of the body is raised.

Description

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This invention relates to a railway vehicle com-prising bogies and a body suspended from such bogies provided with means allowing a controlled rolling movemen-t o~ the body ior tilting it at a sui-table angle in a curve for the com~ort ; of the passengers and for amendment of the guard a~ainst over-turning. The body is suspended from swing arms arranged in a certain angular position in relation to a vertical longitudinal plane through the vehicle. ~he rolling of the body is achieved by tilting actuators.
In order to obtain fully -the desired tilting angle by rolling the body in relation to the bogies~ the swing arms must have such an inclina-tion that the center o~ gravity of the body is raised considerably. The tiltiny is therefore very energy-demanding. r One object of the invention is to relieve the swing ; arms carrying the body and guiding the rolling movement o~ the ', vehicle body from carrying alone the weight o~ said body.
' Another object o the inventlon is to relieve the weight of the body by means of communica-ting hydraulic or pneumatic cylinders. By using hydraulic cylinders a pressure accumulator is connected. In this accumula-tor energy is stored, which energy is used for reducing the energy requirement of ~- the tilting actuators.
In accordance with the above objects, wha-t is being broadly claimed herein is a railway vehicle comprising:
a vehicle body; a bogie ~rovided with a supporting element; a cradle beam on which the vehicle body is resiently mountctl, an(l sw;ntJ arms articulatccl at thcir er~(ls resL~ectiv(~ly to the'supporting elements and to the cradle beam to guide the 3~ vehicle body when the latter ti,lts. ~ctuators arc provided to cause, when actuate(l, lateral tiltiny oE the vchicle ~)ody in relation to the bogie, these actuators heing articulat,e-l at 1(1~77~
their ends to the supporting element and to the cradle beam.
Resilient elemen-ts,articulated at -their ends respectively to the cradle beam and to the supporting element,permanently transmit the load from the cradle beam to the suppor-ting element thereby at least partially relieving the swing arms.
An embodiment of the invention will now be described with respect to the appended drawings wherein:
Figure 1 is a schematic cross-section through part of a body and of a bogie with the necessary means for tilting the body, and Figure 2 schematically illustrates the geometry of the movement of the swing arms and the centre of gravity of the vehicle body.
In Figure 1, 11 designa-tes the lower part of a vehicle body. This vehicle body rests on resilien-t elements13, ~ here in the form of air bellows, which in turn rest on a ;~ cradle beam 12 which can be tilted laterally in relation to a ,!
supporting bogie 16. The cradle beam 12 is movably suspended from supporting elements or cross-beams 18 of the bogie, in the shown embodiment by swing arms 14 and 15 which are pivotally journalled on the cradle beam ]2 and on the cross-beam 18 which is supported by springs 17 on the bogie Erame 16. Furtllermore, ac-tuators 19 for tilting the cradle beam 12 are provided between beams 12 and 18. The actuators 19 can be hydraulic cylinders ~- or jacks.
In Figure 2, each swin~ arm 14 and 15 is represented by force vectors Fl and F2. The swing arms are arranged in such a way with respect to the cross-beam 18 tha-t in normal condition, i.e. when no -tilting is applied between vehicle - body and bogie, they make an angle with each other and their longitudinal axeC. extend to intersect each other at a point P
along the center line L of the vehicle body above the centre of gravity Tp o~ the vehicle body. If it is ass~lmecl that a 1al~7783L
tilting angle C~ is applied between the vehicle body 11 and the bogie 16, the two swing arms 14 and 15, i.e. the force vectors Fl and F2, will aaopt the positions Fl' and F2', as shown in Figure 2. If a line is drawn between -the end points of vectors Fl and F2 and the end points of vectors Fl' and F2', since the distance between this line and the centre of gravity of the vehicle bogie is constant, the geometry then shows that the centre of gravity Tp is lifted vertically a distance ~ 1 in order to attain the tilting angle C~ . The ;
10 . greater the tilting angle C~ that is desired, the greater the degree of elevation of the vehicle body.
According to -the invention, resilient elements 20 and 21 are arranged between the til-table cradle beam 12, which : supports the vehicle body 11, and the supporting elements in the bogie, which in the shown embodiment is the cross-beam 18.
These elements 20 and 21 which relieve the arms 14 and 15, should have such a spring characteristic that the spring force is asconstant as possible during the swinging movements of the cross-beam 12. The resilient elements 20 and 21 suitably 20 consist of air cylinders or hydraulic cylinders which are articulately attached to the beams 12 and 1~. In order to obtain the most uniform relieving force, the cylinders must be connected together so that pressure medium can be transferred between the cylinders 20 and 21 and the relieving system must contain a medium for limiting pressure variations, for example a sufficiently large volume of a compressible pressure medium.
The compressed air cylinders can be constructed so that the entire amount of pressure medium is present in the cylinders 20 and 21 and in a connecting conduit, but the cylinders may also communicate with an auxiliary container 22 wit~ a suitable additional volume. When using hydraulic cylinders, there is ~6~777~1 required a gas-filled additional volume. An auxiliary container 22 is then designed as a pressure accumulator.
Tilting of the vehicle body also involves a change in level, as illustrated in Figure 2. The total pressure medium volume in the two cylinders 20 and 21 thus varies, since the increase in volume of one cylinder is greater than the reduction in volume of the other. When til-ting the cradle beam, pressure medium flows between the cylinders and to or from the auxiliary container. The variations in pressure and thus the relieving force vary with the amount of compressible pressure medium in the system. The size of the cylinders and the pressure level are chosen so that the cylinders 20 and 21 ' transEer the major part of the force between the beams 12 and 18, so that the swingin~ arms 14 and 15 become subs-tantially relieved. A complete relief of load implies a certain risk -~ of instability.
The arrangement according to the invention is, of course, not limited to the embodiment shown here but can be varied in many ways within the scope of the appended claims.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A railway vehicle comprising: a vehicle body;
a bogie having a supporting element; a cradle beam and means resiliently mounting said vehicle body on said cradle beams;
swing arms articulated at the ends thereof, respectively to said supporting element and to said cradle beam to guide said vehicle body upon tilting thereof; actuators articulated at the ends thereof to said supporting element and to said cradle beam to cause, when actuated, lateral tilting of said vehicle body in relation to said bogie, and resilient elements articulated at their ends respectively to said cradle beam and to said supporting element to permanently transmit the load from said cradle beam to said supporting element thereby at least partially relieving said swing arms.

2. A railway vehicle as claimed in claim 1, wherein said resilient elements have a spring characteristic such that the spring force thereof remains substantially constant during the tilting movement of the cradle beam and of the vehicle body.

3. A railway vehicle as claimed in claim 2, wherein said resilient elements relieving said swing arms are pneumatic jacks mounted on each side of the vehicle body with respect to a vertical and longitudinal central plane thereof, and means joining said jacks for transfer of pressure medium therebetween.

4. A railway vehicle as claimed in claim 3, wherein said means include pressure medium lines and a pressure accumulator to which said lines are connected.

5. A railway vehicle according to claim 1, wherein said resilient elements relieving said swing arms are hydraulic cylinders mounted on each side of the vehicle body with respect to a vertical and longitudinal central plane thereof and means joining said cylinders for transfer of pressure medium there-between, said means including pressure medium lines and a partly gas-filled pressure accumulated to which said lines are connected.

6. A railway vehicle as claimed in claims 3, 4 or 5, wherein said resilient elements have a spring characteristic such that the spring force thereof remains substantially constant during the tilting movement of the cross-beam and vehicle body.

7. A railway vehicle comprising: a vehicle body;
two bogies beneath said body with resilient supporting means thereon; two cradle beams and means resiliently mounting said vehicle body on said cradle beams above said supporting means; arm means mounting said cradle beams on said supporting means, respectively, to allow lateral swinging motion of said cradle beams and of said body relative to said bogies; axially extensible actuators articulated at the ends thereof respectively to said supporting means and to said cradle beams to cause, when actuated, lateral tilting of said cradle beams and vehicle body in relation to said bogies; resilient load-relieving elements articulated at their ends respectively to said cradle beams and to said supporting means, said resilient elements being adapted to transfer at least part of the vehicle body load from the cradle beams to the supporting means thereby at least partially relieving said arm means.

8. A railway vehicle as claimed in claim 7, wherein said resilient supporting means comprises supporting beams extending transversely of said vehicle body and resilient means mounting the ends of said supporting beams on said bogies;
wherein said arm means are pairs of rigid generally straight arms, there being one such pair for each cradle beam; each arm being pivoted at their ends respectively to one of said transverse supporting beams and to said cradle beams, and wherein the longitudinal axes of said arms extend to intersect at a point above the center of gravity of said vehicle body along the longitudinal center line thereof when said body stands idle with respect to said bogies.

9. A railway vehicle as claimed in claim 8, wherein said axially extensible actuators are pneumatic jacks.

10. A railway vehicle as claimed in claim 8, wherein said resilient load-relieving elements comprise hydraulic jacks having pressure chambers and means interconnecting said pressure chambers, including a partly gas-filled pressure accumulator.

11. A railway vehicle as claimed in claim 9, wherein said interconnecting means includes a container and piping means joining said container and pressure chambers, said container acting to limit pressure variations in said chambers.

12. A railway vehicle as claimed in claims 7 or 8, wherein said resilient elements have a spring characteristic such that the spring force thereof remains substantially constant during the tilting movement of the cradle beam and of the vehicle body.