Rail vehicle unit with a traction linkage

Abstract

 The present invention relates to a rail vehicle unit comprising a running gear frame (104) of a running gear, a supported vehicle component (111), and a traction linkage element (112.1), the running gear frame (104) defining a longitudinal direction, a transverse direction and a height direction. The running gear frame (104) is substantially H-shaped and comprises two longitudinal beams (104.2) and one transverse beam (104.1) providing a structural connection between the longitudinal beams (104.2) in the transverse direction. The supported vehicle component (111) is supported on the running gear frame (104) via a spring unit. The supported vehicle component (111) and the running gear frame (104) are connected in the longitudinal direction via the traction linkage element (112.1), a first end of the traction linkage element (112.1), in a first articulation location, being articulated to the running gear frame (104) and a second end of the traction linkage element (112.1), in a second articulation location, being articulated to the supported vehicle component (111). The transverse beam (104.1) is a substantially box shaped element formed by a plurality of wall elements (104.3 to 104.6), the traction linkage element (112.1) being received within the transverse beam (104.1) and being connected to a console element (113). The console element (113) reaches into the transverse beam (104.1) and is connected to the supported vehicle component (111).

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a rail vehicle unit, comprising a running gear frame of a running gear, a supported vehicle component, and a traction linkage element, the running gear frame defining a longitudinal direction, a transverse direction and a height direction. The running gear frame is substantially H-shaped and comprises two longitudinal beams and one transverse beam providing a structural connection between the longitudinal beams in the transverse direction. The supported vehicle component is supported on the running gear frame via a spring unit. The supported vehicle component and the running gear frame are connected in the longitudinal direction via the traction linkage element, a first end of the traction linkage element, in a first articulation location, being articulated to the running gear frame and a second end of the traction linkage element, in a second articulation location, being articulated to the supported vehicle component. The present invention further relates to a rail vehicle comprising such a rail vehicle unit.

[0002] Such a rail vehicle unit is known, for example, from EP 0 831 003 B1 (Bohms et al.). Here, a so-called Jacobs bogie is disclosed, wherein the traction linkage is connected to a vertical arm of a coupling used to couple the ends of the two wagon bodies supported on the bogie. The articulation of the traction linkage to the bogie frame is located between two generally box-shaped transverse beams of the running gear, the box shaped transverse beam interfacing the traction linkage providing sufficient strength and bending resistance to take the (considerable) loads introduced via the traction linkage.

[0003] Such a placement of the traction linkage at a low level (in the height direction) has certain advantages regarding the introduction of the reaction forces of the wagon body into the bogie resulting from traction and braking forces. In particular, such a configuration is beneficial in terms of reduced unloading of single wheels at these occasions.

[0004] Such a configuration with a low traction linkage located between two transverse beams may be easily feasible in such a Jacobs bogie, due to its generally large dimension in its longitudinal direction providing sufficient space between the two transverse beams. However, in a generally shorter bogie as the ones supporting one single wagon body causes the problem that there is not sufficient space between the two transverse beams for placing the comparatively long linkage. Furthermore, such a configuration with two transverse beams has the disadvantage that it is comparatively heavy adding to the overall weight of the bogie. Such a high weight, among others, is disadvantageous in terms of the dynamic properties of the vehicle, in particular at high speeds.

[0005] A further type of connection between a running gear and a wagon body is known, for example, from DE 37 01 424 A1 (Weigel). Here, for such a generally shorter bogie supporting one single wagon body, a longitudinally compact swivel pin arrangement is chosen. However, here as well, two transverse beams are supporting the stop elements cooperating with the swivel pin which, again, has the disadvantages regarding the overall weight of the bogie. Furthermore, a considerable play between the wagon body and the bogie is present in the longitudinal direction which is disadvantageous in terms of the running properties of the vehicle, in particular at high speeds.

SUMMARY OF THE INVENTION

[0006] It is thus an object of the present invention to provide a rail vehicle unit as outlined above that, at least to some extent, overcomes the above disadvantages. It is a further object of the present invention to provide a rail vehicle unit that provides improved dynamic properties at an overall lightweight and space-saving configuration.

[0007] The above objects are achieved starting from a rail vehicle unit according to the preamble of claim 1 by the features of the characterizing part of claim 1.

[0008] The present invention is based on the technical teaching that improvement of the dynamic behavior of the running gear, in particular, at high speeds, maybe achieved with an overall lightweight and space-saving configuration if the traction linkage element is integrated or received, respectively, on the inside of one single transverse beam formed as a substantially box shaped element by a plurality of wall elements. It has been found that single box shaped transverse beam may be suitably designed to take the considerable loads introduced via the articulation of the traction linkage element at its inside. Hence, since the two transverse beams may be dispensed with, a very compact and lightweight design is achieved relaxing, to some extent, the strict building space requirements within a modern running gear, in particular for a high-speed application. Furthermore, such a configuration nevertheless allows achieving the beneficial effects of a substantially play-free traction linkage at a very low height level as they have been outlined initially.

[0009] Hence, according to one aspect, the present invention relates to a rail vehicle unit comprising a running gear frame of a running gear, a supported vehicle component, and a traction linkage element, the running gear frame defining a longitudinal direction, a transverse direction and a height direction. The running gear frame is substantially H-shaped and comprises two longitudinal beams and one transverse beam providing a structural connection between the longitudinal beams in the transverse direction. The supported vehicle component is supported on the running gear frame via a spring unit. Furthermore, the supported vehicle component and the running gear frame are connected in the longitudinal direction via the traction linkage element, a first end of the traction linkage element, in a first articulation location, being articulated to the running gear frame and a second end of the traction linkage element, in a second articulation location, being articulated to the supported vehicle component. The transverse beam is a substantially box shaped element formed by a plurality of wall elements, the traction linkage element being received within the transverse beam and being connected to a console element. The console element reaches into the transverse beam and is connected to the supported vehicle component.

[0010] It will be appreciated that the structural connection between the two longitudinal beams, apart from the transverse beam, may be provided by further structural components. Preferably, however, at least in the (longitudinally) central area, the single transverse beam forms a single structural connection between the two longitudinal beams such that a very compact and lightweight configuration is achieved. Hence, preferably, the transverse beam is formed by a front wall element, a rear wall element, an upper wall element and a lower wall element, in the area of the transverse beam, the structural connection between the longitudinal beams being exclusively provided via the front wall element, the rear wall element, the upper wall element and the lower wall element.

[0011] These wall elements may have any suitable configuration. For example, at least single ones of these wall elements may be formed as sandwich elements comprising two or more layers. A favorably space-saving and easily manufactured configuration and is achieved if the front wall element and/or the rear wall element are exclusively formed by a sheet metal element. This is particularly the case if the sheet metal element is a single layer element easing manufacture considerably.

[0012] Structural stability of such a single transverse beam receiving the traction linkage at its inside generally may be achieved by any suitable means. Preferably, the transverse beam, in the region of the traction linkage element, has a longitudinally salient section within at least one of a front wall section and a rear wall section of the transverse beam. Such a salient section (in particular, if this wall section is also supporting or forming the interface to the traction linkage element) not only improves the introduction and support of the loads within the transverse beam, it furthermore locally provides more space for receipt of the traction linkage element while keeping the remainder of the transverse beam compact.

[0013] It will be appreciated that, with certain embodiments of the invention achieving a very good design regarding structural stability at compact dimensions, the salient section, in the longitudinal direction, provides a maximum longitudinal distance between the front wall section and the rear wall section which is 105% to 130% of a minimum longitudinal distance between the front wall section and the rear wall section. Preferably, a value of 110% to 120% of the minimum longitudinal distance is chosen, more preferably 110% to 115% of the minimum longitudinal distance.

[0014] The transverse beam may be a simple generally hollow component. Preferably, the transverse beam, in the region of the traction linkage element, has at least one lateral wall element confining a receptacle for the traction linkage element, the lateral wall element being spaced from an adjacent one of the longitudinal beams. Such a lateral wall element may serve as an inner reinforcement element allowing compact dimensions of the transverse beam at improved structural stability.

[0015] The respective lateral wall element may be rigidly connected only to one single of the adjacent walls of the transverse beam. However, preferably, it is connected to at least two of these adjacent walls to obtain, for example, the desired reinforcement properties. Hence, with certain embodiments of the invention, the transverse beam is formed by a wall element set consisting of a front wall element, a rear wall element, an upper wall element and a lower wall element, the lateral wall element forming an inner reinforcement element of the transverse beam rigidly connected to at least two, preferably at least three, more preferably all, of the walls of the wall element set.

[0016] The lateral wall element may have any suitable shape selected, for example, as a function of the desired or necessary force flux within the transverse beam. Particularly good reinforcement properties are achieved if the lateral wall element, in a view along the height direction is substantially V-shaped. Such a configuration has the advantage that, for example, torsional rigidity of the transverse beam is greatly improved. Furthermore, preferably, a root section of the V-shaped lateral wall element is arranged such that it faces away from the traction linkage element. In this case, a compact configuration is achieved with a concentrated reinforcement in the area of the traction linkage. Furthermore, the root section of the V-shaped lateral wall element may serve as a structurally highly stable interface for a transverse damping element connected to the traction linkage element and damping transverse motion of the traction linkage element.

[0017] With certain embodiments of the invention the transverse beam, in the region of the traction linkage element, has at least one lateral stop element adapted to limit lateral motion of the traction linkage element in the transverse direction. A very simple arrangement which is easy to manufacture is achieved if the lateral stop element is at least partially located outside the transverse beam.

[0018] Preferably, the lateral stop element is located in the region of an upper wall section of the transverse beam. Here, preferably, the lateral stop element transversely abuts against an edge section of the upper wall section such that a favorable introduction of the transverse forces into the upper wall section is achieved predominantly resulting in sheer loads and largely avoiding bending loads in the upper wall section.

[0019] Furthermore, in addition or as an alternative, it may be provided that the lateral stop element protrudes, in the height direction, from the transverse beam. In this case, preferably, at least one lateral support element is associated to the lateral stop element, the lateral support element extending in the transverse direction. By this means, proper introduction and support of bending loads into the upper wall of the transverse beam is achieved. This effect is improved if the lateral support element reaches up to the region of an inner reinforcement element located within the transverse beam.

[0020] The points of articulation of the traction linkage element, in the height direction, may be located at any desired height level. Preferably, they are located as low as possible in order to reduce pitch moments about the wheel-rail contact points which lead to undesired wheel unloading at the leading wheel unit (when accelerating) or at the trailing wheel unit (when braking) which increases the derailment risk.

[0021] Furthermore, preferably, the points of articulation are located close to the height level of the wheel unit axis to reduce the pitching moment (about the wheel axis) and, hence, the disposition of the running gear to develop pitching oscillation (i.e. oscillation about a pitching axis running in the transverse direction) of the running gear frame, since such pitching oscillation is adverse in terms of running stability, derailment risk and passenger comfort, in particular, at high speeds.

[0022] Hence, preferably, in a variant of the invention with a running gear frame having a nominal loading and being supported on a wheel unit adapted to run on a track having a track level, the wheel unit defines a wheel unit axis having, in the height direction, a first height level above the track level. Here, the first articulation location of the traction linkage element, in the height direction, is located at a second height level above the track level, wherein the second height level, at least under the nominal loading, deviates from the first height level by less than 30% of the first height level. Preferably, the deviation is less than 20%, more preferably from 0% to 10%, of the first height level.

[0023] In addition or as an alternative, the second articulation location of the traction linkage element, in the height direction, is located at a third height level above the track level, the third height level, at least under the nominal loading, deviating from the first height level by less than 30%, preferably less than 20%, more preferably from 0% to 10%, of the first height level.

[0024] With either one of these solutions, in particular, with their combination, a particularly good compromise between the reduced risk of derailment, the reduction of the disposition to develop pitching oscillation when accelerating or breaking, and the track clearance (relevant, among others, in terms of the aerodynamic properties of the running gear) is achieved.

[0025] With certain preferred embodiment, the second height level and the third height level, at least under the nominal loading, are substantially identical, such that the above advantages are achieved to their maximum degree. With certain embodiments putting a focus on the reduction of pitch moments, the first height level is substantially identical to the second and third height level.

[0026] It will be appreciated that the console element may have any suitable design to provide proper connection to the supported vehicle component. Preferably, the console element is an elongated arm element extending in the height direction. The interface to the traction linkage element may also be designed in any desired suitable way. Preferably, the console element, at the second articulation location, has a forked interface end receiving the second end of the traction linkage element. Such a solution is particularly beneficial in terms of proper load transmission.

[0027] With certain embodiments of the invention the console element is connected to a damping element, the damping element being further connected to the running gear frame and damping transverse motion between the running gear frame and the supported vehicle component, thereby relieving the secondary suspension from fulfilling this task. The damping element may be located at any available and suitable location. Preferably, as already indicated above, the damping element may be received within the transverse beam to achieve a very compact design.

[0028] The supported vehicle component may be the wagon body itself. However, with certain other advantageous variants of the invention, the supported vehicle component is a bolster of the running gear, the bolster being adapted to be connected to a wagon body to be supported. Such a solution has the advantage that the running gear including the entire suspension system and a up to the interface with the wagon body may be pre-tested.

[0029] With certain further embodiments of the invention a favorable, particularly lightweight design is achieved in providing at least one of the wall elements of the transverse beam as a weight reduced wall element showing at least one otherwise nonfunctional weight reduction recess at a less mechanically stressed location. The less mechanically stressed location is a location where, in a reference wall element and under any load collective to be expected under normal operation of the rail vehicle unit, a reference stress occurs that is less than 5% of a maximum reference stress (that occurs in the reference element). Preferably, the reference stress is less than 10%, more preferably less than 15% to 20%, of the maximum reference stress. The reference wall element, apart from having a continuous, recess-free wall design, is substantially identical to the corresponding wall element of the transverse beam showing the weight reduction recess and replaces this recessed wall element. Furthermore, the maximum reference stress is a maximum mechanical stress occurring in the reference wall element under the respective one of the load collectives.

[0030] It will be appreciated that the reference stress and the maximum reference stress both are considered for the same load collective, i.e. at the same loading situation of the transverse beam, such that different maximum reference stresses may have to be considered depending on the loading situation. Hence, while certain locations may fulfill the requirements for being identified as a less mechanically stressed location under a first load collective (to be expected under normal operation of the vehicle and, hence, to be considered), these conditions may not be met under a further, different load collective (also to be expected under normal operation and, hence, also to be considered). In such a case, the specific location does not qualify as such a less mechanically stressed location in the sense of the present invention, and, hence, no recess is placed at this location. It will be further appreciated that, with certain embodiments of the invention, only those load collectives will have to be considered wherein maximum stresses are to be expected during normal operation of the vehicle.

[0031] It will be appreciated that such a weight reduction recess insofar distinguishes from other conventional recesses within components or wall elements as its single purpose is the weight reduction achieved. Hence, for this reason, such a weight reduction recess distinguishes from other recesses eventually present for providing access to another component of the vehicle or for immediately receiving further components of the vehicle.

[0032] It will be further appreciated that this weight reduction concept may be applied to any component or wall element, respectively, of the running gear. Preferably, the at least one weight reduced wall element is an upper wall element and/or a lower wall element of the transverse beam. In addition or as an alternative the at least one weight reduced wall element is an inner reinforcement wall element of the transverse beam such as, for example, the one confining the receptacle for the traction linkage element has outlined above. Furthermore, in addition or as an alternative, the at least one weight reduced wall element is a support element of a lateral stop element of the transverse beam such as, for example, the one as outlined above.

[0033] It will be appreciated that the present invention may be used for any desired rail vehicle operating at any desired nominal operating speed. However, the beneficial effect of the present invention or a particularly visible in the high-speed operations. Hence, preferably, the running gear it is adapted for a nominal operating speed above 250 km/h, preferably above 300 km/h, more preferably above 350 km/h.

[0034] The present invention furthermore relates to a rail vehicle with a rail vehicle unit according to the invention as it has been outlined above.

[0035] Further embodiments of the present invention will become apparent from the dependent claims and the following description of preferred embodiments which refers to the appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] 

Figure 1

is a schematic perspective top view of a preferred embodiment of a running gear according to the present invention comprising a preferred embodiment of the running gear frame according to the present invention and used in a preferred embodiment of the rail vehicle according to the present invention;

Figure 2

is a schematic perspective top view of the running gear frame of Figure 1;

Figure 3

is a schematic, partially sectional perspective top view of the running gear frame of Figure 1;

Figure 4

sectional view of a detail of the running gear frame of Figure 1 (along line IV-IV of Figure 1);

Figure 5

is a schematic, partially sectional perspective top view of a further preferred embodiment of a running gear frame according to the present invention used the rail vehicle of Figure 1 (in a view corresponding to the one of Figure 3).

DETAILED DESCRIPTION OF THE INVENTION

First Embodiment

[0037] With reference to Figures 1 to 4 a preferred embodiment of a rail vehicle 101 according to the present invention comprising a first preferred embodiment of a running gear 102 according to the invention will now be described in greater detail. In order to simplify the explanations given below, an xyz-coordinate system has been introduced into the Figures, wherein (on a straight, level track) the x-axis designates the longitudinal direction of the running gear 102, the y-axis designates the transverse direction of the running gear 102 and the z-axis designates the height direction of the running gear 102.

[0038] The vehicle 101 is a high-speed rail vehicle with a nominal operating speed above 250 km/h, more precisely above 300 km/h. The vehicle 101 comprises a wagon body (not shown) supported by a suspension system on the running gear 102. The running gear 102 comprises two wheel units in the form of wheel sets 103 supporting a preferred embodiment of a running gear frame 104 according to the invention via a primary spring unit 105. The running gear frame 104 supports the wagon body via a secondary spring unit 106.

[0039] Each wheel set 103 and is driven by a drive unit 107. The drive unit 107 comprises a motor unit 108 (suspended to the running gear frame 104) and a gearing 109 (sitting on the shaft of the wheel set 103) connected via a motor shaft 110. Both drive units 107 are of substantially identical design and arranged substantially symmetrically with respect to the center of the running gear frame 104.

[0040] As can be seen best from Figures 2 and 3, the running gear frame 104 is of generally H-shaped design with a middle section in the form of a transverse beam 104.1 located between the wheel sets 103 and rigidly connecting two longitudinal beams 104.2. The interface of the running gear 102 to the wagon body (not shown) is formed by a bolster 111 rigidly connected to the wagon body and supported on the running gear frame 104 via the secondary spring unit 106.

[0041] As can be seen best from Figure 4, the transmission of forces in the longitudinal direction (x-direction) between the wagon body and the running gear frame 104 is provided via a traction linkage 112 comprising a traction linkage element 112.1. A first end of the traction linkage element 112.1 is articulated to the transverse beam 104.1 at a first articulation location 112.2, while a second end of the traction linkage element 112.1 is articulated, at a second articulation location 112.3, to a console element in the form of an elongated arm 113 of the bolster 111.

[0042] As can be seen best from Figures 3 and 4, the transverse beam 104 is a substantially box shaped element formed by a plurality of wall elements, namely (seen in the positive x-direction) a front wall element 104.3 and a rear wall element 104.4 as well as (seen in the z- direction) an upper wall element 104.5 and a lower wall element 104.6. It is to be noted that Figure 3 shows a partially sectional view of the running gear frame 104 where part of the upper wall element 104.5 as well as a part of an upper wall of the right longitudinal beam 104.2 have been removed for providing a better overview over the inner structure of the transverse beam 104.1 and the longitudinal beams 104.2.

[0043] The traction linkage element 112.1 is received within a centrally located receptacle 104.7 of the transverse beam 104.1. The receptacle 104.7 is confined by the wall elements 104.3 to 104.6 as well as by two lateral wall elements 104.8 located on both sides of the center of the running gear frame 104. Each lateral wall element 104.8 is spaced from the respective adjacent longitudinal beam 104.2 and is substantially V-shaped in a view along the height direction, a root section 104.9 of the lateral wall element 104.8 facing away from the traction linkage element 112.1 and towards the associated longitudinal beam 104.2.

[0044] These lateral wall elements 104.8 form inner reinforcement wall elements of the transverse beam 104.1. To this end, the lateral wall elements are rigidly connected to the adjacent wall elements 104.3 to 104.6 of the transverse beam 104.1. This configuration has the advantage that, for example, torsional rigidity of the transverse beam 104.1 about the transverse axis (y-direction) is greatly improved. Furthermore, a compact configuration is achieved with a concentrated reinforcement in the area of the traction linkage 112.

[0045] The root section 104.9 of one of the lateral wall elements 104.8 further serves as a structurally highly stable interface for a transverse damping element (only schematically indicated in Figure 3 by its line of action 114) connected to either the traction linkage element 112.1 or, preferably, to the corresponding interface of the console 113. The damping element 114 damps motion in the transverse direction (y-direction) between the running gear frame 104 and the bolster 111. It will be appreciated that, with other embodiments, of the invention such a damping element may be provided at each side of the running gear.

[0046] The connection between the traction linkage element 112.1 and the console 113 (at the second articulation location 112.3) is provided via a fork shaped end section 113.1 reaching through an opening 104.10 of the upper wall element 104.5 down into the receptacle 104.7 such that each of its free ends is rigidly connected (e.g. via screws or the like) to a free end of an axle element 112.4 of the traction linkage element 112.1. The axle element 112.2 is received within an elastic bearing (e.g. a conventional rubber bearing) of the traction linkage element 112.1 allowing relative motion between the traction linkage element 112.1 and the axle element 112.2.

[0047] A similar connection is provided at the other, first end of the traction linkage element 112.1 (i.e. at the first articulation location 112.2), where each of the free ends of an further axle element 112.5 (elastically held within the traction linkage element 112.1) is rigidly connected (e.g. via screws or the like) to an adjacent interface element 104.11 rigidly mounted to the front wall 104.3 of the transverse beam 104.1.

[0048] As can be seen from Figure 2 and 3, a lateral stop device 115 comprising two lateral stop elements 115.1 is provided to limit lateral motion of the bolster 111 with respect to the running gear frame 104 (and, hence, also lateral motion of the traction linkage element 112.1) in the transverse direction. The lateral stop elements 115.1 are provided laterally at both sides of the opening 104.10 in the upper wall element 104.5 and are partially located outside the transverse beam 104.1.

[0049] Each lateral stop element 115.1 further reaches into the receptacle 104.7 and transversely abuts against an edge section of the upper wall element 104.5 such that a favorable introduction of the transverse forces into the upper wall element 104.5 is achieved predominantly resulting in sheer loads and largely avoiding bending loads in the upper wall element 104.5.

[0050] Furthermore, for the part of the respective lateral stop element 115.1 protruding (in the height direction) from the transverse beam 104.1, two lateral support elements 115.2 are provided. These lateral support elements 115.2 extending in the transverse direction. By this means, proper introduction and support of bending loads into the upper wall 104.5 of the transverse beam 104.1 is achieved. This effect is further improved since the respective lateral support element 115.2 reaches up to the region of the associated inner reinforcement element 104.8 located within the transverse beam (as becomes apparent best from Figure 3).

[0051] As can be seen Figure 2 and 3, a drive support unit 116 for each one of the drive units 107 is mounted to the (transversally) central part of the front wall element 104.3 and the rear wall element 104.4, respectively. Each drive support unit 116 comprises a lower support structure 116.1 and a plurality of drive support arms 115.2 mounted thereon. Each of the drive support arms 116.2 forms a hook-shaped interface element for the drive unit 107 to support the latter.

[0052] It will be appreciated that the (transversally) central part of the upper wall element 104.5 and of the lower wall element 104.6 (in the longitudinal direction) extends beyond the front wall element 104.3 and the rear wall element 104.4, respectively, such that it also forms a part of the respective drive support unit 116 (thereby providing firm connection between the transverse beam 104.1 and the drive support unit 116). However, with other embodiments of the invention, if present at all, separate top and bottom closures may be provided.

[0053] The running gear frame 104 is a weight reduced yet structurally highly stable component, weight reduction while keeping structural stability being achieved by several, independently applicable approaches (yet these approaches are preferably combined to achieve the maximum effect). The weight reduction of the running gear frame 104 achieved by these means is not only beneficial in terms of the overall energy consumption of the vehicle 101.

[0054] It is also advantageous in terms of the running stability of the vehicle 101 at high speeds where a low moment of inertia, in particular about the yaw axis (i.e. the height axis) of the running gear 102 is favorable.

[0055] One of these approaches is to reduce the structure of the transverse beam to a minimum by providing the structural connection between the two longitudinal beams 104.2 in the (longitudinally) central area of the running gear frame 104 exclusively by the four wall elements 104.3 to 104.6. Hence, a very compact and lightweight configuration is achieved by simply avoiding a conventional structure with two generally box-shaped transverse beams.

[0056] In the present example, a further reduction in weight and complexity of the design is achieved by using simple sheet metal elements for the four wall elements 104.3 to 104.6. It will however be appreciated that, with other embodiments of the invention, sandwich elements all the like may be used for the wall elements 104.3 to 104.6.

[0057] Structural stability of this single transverse beam 104.1 receiving the traction linkage elements 112.1 at its inside is, on the one hand, achieved via the inner reinforcement wall elements 104.8 and has been described above.

[0058] Furthermore, structural stability of the transverse beam 104.1 is increased (without noticeably increasing weight) by a longitudinally salient section 104.12 within the front wall section 104.3 and a longitudinally salient section 104.13 within the rear wall section 104.4 of the transverse beam 104.1. Both salient sections 104.12, 104.13 are substantially centrally located (in the transverse direction) and are formed in the area of the receptacle 104.7.

[0059] These salient sections 104.12, 104.13 (in particular, the salient section 104.12 forming the interface to the traction linkage element 112.1) improve the introduction and support of the loads within the transverse beam 104.1. Furthermore, apart from increasing the bending resistance and the torsional resistance (via an increase in the respective second moment of area of the transverse beam 104.1), the salient sections 104.12, 104.13 also locally provide more space for receipt of the traction linkage element 112.1 while keeping the remainder of the transverse beam 104.1 compact.

[0060] As can be seen from Figure 3, the salient sections 104.12, 104.13, in the longitudinal direction, provide a maximum longitudinal distance LD_max between the front wall element 104.3 and the rear wall element 104.4 which is 110% of a minimum longitudinal distance LD_min between the front wall element 104.3 and the rear wall section 104.4. In the present example, this LD_min is in the longitudinal distance between the front wall element 104.3 and the rear wall section 104.4 transversely outside of the salient sections 104.12, 104.13, which is in particular present at the respective connection between the front wall section 104.3 and the rear wall section 104.4 and the longitudinal beam 104.2.

[0061] The salient sections104.12, 104.13, in the transverse direction, extend over a transverse distance TDS of about 45% of the inner transverse distance TDL between the longitudinal beams 104.2. Hence, by this means, only a moderate increase in the size of the transverse beam 104.1 is achieved while obtaining the above advantages.

[0062] It will be appreciated that, with other embodiments of the invention, the transverse distance TDS may vary from 25% to 65% of the longitudinal beam distance TDL, preferably from 35% to 55% of the longitudinal beam distance TDL, more preferably from 40% to 50% of the longitudinal beam distance TDL.

[0063] A further (nevertheless individually applicable) approach followed in the present example for reducing the weight of the running gear frame 104 is to use a plurality of weight reduced wall elements at several locations within the running gear frame 104 as will be explained in the following.

[0064] This weight reduction approach is based on the idea to modify the structure of the transverse beam (compared to conventional running gear frames of this type) insofar as each of these weight reduced wall elements shows at least one (otherwise nonfunctional) weight reduction recess at a less mechanically stressed location.

[0065] As can be seen, in particular, from Figure 2 to 4 the present running gear frame 104 shows such weight reduction recesses 104.14 in the upper wall element 104.5, the lower wall element 104.6 and the reinforcement wall elements 104.8 of the transverse beam 104.1 as well as within inner reinforcement elements 104.15 of the longitudinal beams 104.2. Furthermore, such weight reduction recesses 115.3 also provided in the natural support elements 115.2. Finally, such weight reduction recesses 116.3 also provided within the lower support structure 116.1 and within the drive support arms 116.2 of the drive support unit 116.

[0066] It will be further appreciated that such a weight reduction recess 104.14, 115.3, 116.3, typically, insofar distinguishes from other conventional recesses within components or wall elements as its single purpose is the weight reduction achieved. Hence, for this reason, such a weight reduction recess 104.14, 115.3, 116.3 distinguishes from other recesses (such as, for example, the opening 104.10) eventually present for (typically imperatively) providing access to another component of the vehicle or for immediately receiving further components of the vehicle.

[0067] As has been outlined above, the less mechanically stressed location for the weight reduction recess 104.14, 115.3, 116.3, is a location where, in a reference wall element and under any load collective LC_i to be expected under normal operation of the rail vehicle 101, a reference stress RS_i occurs that is less than 20% of a maximum reference stress RS_max (that occurs in the reference element). The reference wall element, apart from having a continuous, recess-free wall design, is substantially identical to the corresponding wall element of the running gear frame 104 showing the weight reduction recess 104.14, 115.3, 116.3 and replaces this recessed wall element. Furthermore, the maximum reference stress RS_max,i is a maximum mechanical stress occurring in the reference wall element under the respective one of the load collectives LC_i.

[0068] It will be appreciated that the reference stress RS_i and the maximum reference stress RS_max,i both are considered for the same load collective LC_i, i.e. at the same loading situation of the running gear frame 104, such that different maximum reference stresses RS_max,i may have to be considered depending on the loading situation. Hence, while certain locations may fulfill the requirements for being identified as a less mechanically stressed location under a first load collective LC₁, (to be expected under normal operation of the vehicle and, hence, to be considered), these conditions may not be met under a further, different load collective LC₂ (also to be expected under normal operation and, hence, also to be considered). In such a case, the specific location does not qualify as such a less mechanically stressed location in the sense of the present invention, and, hence, no recess is placed at this location. It will be further appreciated that, with certain embodiments of the invention, only those load collectives LC_i will have to be considered wherein maximum stresses are to be expected during normal operation of the vehicle 101.

[0069] A further advantage of the present embodiment of the rail vehicle 101 lies within the arrangement of the traction linkage 112 and its points of articulation providing advantageous transmission of the longitudinal forces resulting when accelerating or braking the vehicle 101 as will be outlined in the following.

[0070] Under nominal loading of the rail vehicle 101, the articulation locations 112.2 and 112.3 (more precisely the pivot axis) of the traction linkage element 112.1, in the height direction, are located at a second and a third height level above a track level (of the track as indicated by the dashed contour 117 in Figure 1) which is substantially identical to the first height level of the wheel unit axis of the wheel units 103.

[0071] This arrangement of the articulation locations 112.2 and 112.3 reduces the pitching moment (about the wheel axis) and, hence, the disposition of the running gear 102 to develop pitching oscillation (i.e. oscillation about a pitching axis running in the transverse direction) of the running gear frame 104. This is beneficial since such pitching oscillation is adverse in terms of running stability, derailment risk and passenger comfort, in particular, at high speeds.

[0072] Furthermore, this solution has the advantage that the articulation locations 112.2 and 112.3 are located comparatively low (in the height direction) such that pitch moments about the wheel-rail contact points are reduced, which may lead to undesired wheel unloading at the leading wheel unit 103 (when accelerating) or at the trailing wheel unit 103 (when braking) which increases the derailment risk.

[0073] With the present arrangement a particularly good compromise between the reduced risk of derailment, the reduction of the disposition to develop pitching oscillation when accelerating or breaking, and the track clearance (relevant, among others, in terms of the aerodynamic properties of the running gear) is achieved.

[0074] It will be appreciated that, in the present example, connection between the components of the running gear frame 104 is provided using a welding process. However, with other embodiment of the invention, this technique or other connecting techniques may be used either alone or in arbitrary combinations. Furthermore, sheet metal elements as well as cast or forged elements may be used either alone or in arbitrary combinations for the running gear frame.

Second embodiment

[0075] With reference to Figure 5 a further preferred embodiment of a running gear 202 according to the invention comprising a preferred embodiment of the running gear frame 204 will be described in the following. The running gear 202 is also used in the vehicle 101. It will be appreciated that the running gear 202 and, in particular, the running gear frame 204, in their basic design and functionality largely correspond to the running gear 102 and the running the frame 104, such that only the differences will be discussed here. In particular, like components are given the same reference numerals increased by the value 100. With respect to the features and properties of these components explicit reference is made to the explanations given above unless explicit deviating statements are made in the following in this respect.

[0076] The only difference between the running gear 202 and the running gear 102 is that the running gear 202 is a non-driven running gear having no drive unit supported therein. Hence, instead of the two drive support units 116, the running gear 202 comprises two brake support units 216 each adapted to support a brake unit (not shown in detail).

[0077] As can be seen Figure 5, a brake support unit 216 for each one of the brake units is mounted to the (transversally) central part of the front wall element 204.3 and the rear wall element 204.4, respectively. Each brake support unit 216 comprises a lower support structure 216.1 and a plurality of brake support arms 216.2 mounted thereon. Each of the brake support arms 216.2, at its free end, carries a cast interface element 216.4 for the brake unit to support the latter.

[0078] It will be appreciated that, here as well, the (transversally) central part of the upper wall element 204.5 and of the lower wall element 204.6 (in the longitudinal direction) extends beyond the front wall element 204.3 and the rear wall element 204.4, respectively, such that it also forms a part of the respective brake support unit 216 (thereby providing firm connection between the transverse beam 104.1 and the brake support unit 216). However, with other embodiments of the invention, if present at all, separate top and bottom closures may be provided.

[0079] As can be seen from Figure 5, a web element 216.5 of the respective support arm 216.2 is provided with a weight reduction recess 216.3 at a less mechanically stressed location fulfilling the requirements as outlined above in the context of the first embodiment. Furthermore, the interface element 216.4 also is provided with a weight reduction recess 216.3 at a less mechanically stressed location fulfilling the requirements as outlined above in the context of the first embodiment. Hence, in this respect, explicit reference is made to the explanations given above.

[0080] Although the present invention in the foregoing has only a described in the context of high-speed rail vehicles, it will be appreciated that it may also be applied to any other type of rail vehicle in order to overcome similar problems with respect to a simple solution for generally vibrational problems, such as running stability problems and acoustic problems.

Claims

1. A rail vehicle unit, comprising

- a running gear frame (104; 204) of a running gear,

- a supported vehicle component (111), and

- a traction linkage element (112.1);

- said running gear frame (104; 204) defining a longitudinal direction, a transverse direction and a height direction;

- said running gear frame (104; 204) being substantially H-shaped and comprising two longitudinal beams (104.2) and one transverse beam (104.1; 204.1) providing a structural connection between said longitudinal beams (104.2) in said transverse direction;

- said supported vehicle component (111) being supported on said running gear frame (104; 204) via a spring unit;

- said supported vehicle component (111) and said running gear frame (104; 204) being connected in said longitudinal direction via said traction linkage element (112.1), a first end of said traction linkage element (112.1), in a first articulation location, being articulated to said running gear frame (104; 204) and a second end of said traction linkage element (112.1), in a second articulation location, being articulated to said supported vehicle component (111);
characterized in that

- said transverse beam (104.1; 204.1) is a substantially box shaped element formed by a plurality of wall elements (104.3 to 104.6; 204.3 to 204.6);

- said traction linkage element (112.1) being received within said transverse beam (104.1; 204.1) and being connected to a console element (113);

- said console element (113) reaching into said transverse beam (104.1; 204.1) and being connected to said supported vehicle component (111).

2. The rail vehicle unit according to claim 1, wherein

- said transverse beam (104.1; 204.1) is formed by a front wall element (104.3; 204.3), a rear wall element (104.4; 204.4), an upper wall element (104.5; 204.5) and a lower wall element (104.6; 204.6);

- in the area of said transverse beam (104.1; 204.1), said structural connection between said longitudinal beams (104.2) being exclusively provided via said front wall element (104.3; 204.3), said rear wall element (104.4; 204.4), said upper wall element (104.5; 204.5) and said lower wall element (104.6; 204.6).

3. The rail vehicle unit according to claim 2, wherein

- said front wall element (104.3; 204.3) and/or said rear wall element (104.4; 204.4) are exclusively formed by a sheet metal element;

- said sheet metal element, in particular, being a single layer element.

4. The rail vehicle unit according to any one of claims 1 to 3, wherein

- said transverse beam (104.1; 204.1), in the region of said traction linkage element (112.1), has a longitudinally salient section (104.12,104.13) within at least one of a front wall section and a rear wall section;

- said salient section (104.12, 104.13), in particular, in said longitudinal direction, providing a maximum longitudinal distance between said front wall section and said rear wall section which is 105% to 130%, preferably 110% to 120%, more preferably 110% to 115%, of a minimum longitudinal distance between said front wall section and said rear wall section.

5. The rail vehicle unit according to any one of claims 1 to 4, wherein

- said transverse beam (104.1; 204.1), in the region of said traction linkage element (112.1), has at least one lateral wall element (104.8) confining a receptacle (104.7) for said traction linkage element (112.1);

- said lateral wall element (104.8) being spaced from an adjacent one of said
longitudinal beams (104.2),
wherein, in particular,

- said transverse beam (104.1; 204.1) is formed by a wall element set consisting of a front wall element (104.3; 204.3), a rear wall element (104.4; 204.4), an upper wall element (104.5; 204.5) and a lower wall element (104.6; 204.6), said lateral wall element (104.8) forming an inner reinforcement element of said transverse beam (104.1; 204.1) rigidly connected to at least two, preferably at least three, more preferably all, of said walls of said wall element set,
and/or

- said lateral wall element (104.8), in a view along said height direction is substantially V-shaped, a root section of said V-shaped lateral wall element (104.8), in particular, facing away from said traction linkage element (112.1).

6. The rail vehicle unit according to any one of claims 1 to 5, wherein

- said transverse beam (104.1; 204.1), in the region of said traction linkage element (112.1), has at least one lateral stop element (115.1) adapted to limit lateral motion of said traction linkage element (112.1) in said transverse direction, wherein, in particular,

- said lateral stop element (115.1) is at least partially located outside said
transverse beam (104.1; 204.1)
and/or

- said lateral stop element (115.1) is located in the region of an upper wall section
of said transverse beam (104.1; 204.1)
and/or

- said lateral stop element (115.1) protrudes, in said height direction, from said transverse beam (104.1; 204.1), at least one lateral support element (115.2) being associated to said lateral stop element (115.1), said lateral support element (115.2) extending in said transverse direction, in particular up to the region of an inner reinforcement element located within said transverse beam (104.1; 204.1).

7. The rail vehicle unit according to any one of claims 1 to 6, wherein

- said running gear frame (104; 204) has a nominal loading and is supported on a wheel unit (103) adapted to run on a track having a track level;

- said wheel unit (103) defining a wheel unit (103) axis having, in said height
direction, a first height level above said track level,
wherein

- said first articulation location of said traction linkage element (112.1), in said height direction, is located at a second height level above said track level, said second height level, at least under said nominal loading, deviating from said first height level by less than 30%, preferably less than 20%, more preferably from 0% to 10%, of said first height level.
and/or

- said second articulation location of said traction linkage element (112.1), in said height direction, is located at a third height level above said track level, said third height level, at least under said nominal loading, deviating from said first height level by less than 30%, preferably less than 20%, more preferably from 0% to 10%, of said first height level.

8. The rail vehicle unit according to claim 7, wherein

- second height level and said third height level, at least under said nominal loading, are substantially identical;
said first height level, in particular, being substantially identical to said second and third height level.

9. The rail vehicle unit according to any one of claims 1 to 8, wherein

- said console element (113) is an elongated arm element extending in said height direction;

- said console element (113) at said second articulation location having a forked interface end receiving said second end of said traction linkage element (112.1).

10. The rail vehicle unit according to any one of claims 1 to 9, wherein

- said console element (113) is connected to a damping element (114);

- said damping element (114) being further connected to said running gear frame (104; 204) and damping transverse motion between said running gear frame (104; 204) and said supported vehicle component (111);

- said damping element (114), in particular, being received within said transverse beam (104.1; 204.1).

11. The rail vehicle unit according to any one of claims 1 to 10, wherein

- said supported vehicle component (111) is a bolster of said running gear;

- said bolster being adapted to be connected to a wagon body.

12. The rail vehicle unit according to any one of claims 1 to 11, wherein

- at least one of said wall elements of said transverse beam (104.1; 204.1) is a weight reduced wall element showing at least one otherwise nonfunctional weight reduction recess (104.14, 115.3, 116.3; 216.3) at a less mechanically stressed location;

- said less mechanically stressed location being a location where, in a reference wall element and under any load collective to be expected under normal operation of said rail vehicle unit, a reference stress occurs that is less than 5%, preferably less than 10%, more preferably less than 15% to 20%, of a maximum reference stress;

- said reference wall element, apart from having a continuous, recess-free wall design, being substantially identical to and replacing said wall element of said transverse beam (104.1; 204.1) showing said weight reduction recess (104.14, 115.3, 116.3; 216.3);

- said maximum reference stress being a maximum mechanical stress occurring in said reference wall element under the respective one of said load collectives.

13. The rail vehicle unit according to claim 12, wherein

- said at least one weight reduced wall element is an upper wall element (104.5; 204.5) and/or a lower wall element (104.6; 204.6) of said transverse beam (104.1; 204.1)
and/or

- said at least one weight reduced wall element is an inner reinforcement wall
element (104.8) of said transverse beam (104.1; 204.1)
and/or

- said at least one weight reduced wall element is a support element of a lateral stop element (115.1) of said transverse beam (104.1; 204.1).

14. The rail vehicle unit according to any one of claims 1 to 13, wherein it is adapted for a nominal operating speed above 250 km/h, preferably above 300 km/h, more preferably above 350 km/h.

15. A rail vehicle with a rail vehicle unit (102) according to any one of claims 1 to 14.

Drawing