LONG SUPPORT FOR A RAIL VEHICLE BODY

Description

Technical field

[0001] The invention relates to a longitudinal beam for a rail vehicle car body. State of the art

[0002] Rail vehicles, especially passenger vehicles, are frequently manufactured today as self-supporting metal structures using a so-called integral construction method. In this method, a car body is assembled from individual large components such as the underframe, walls, roof, and end walls, all made of extruded lightweight metal profiles. Both horizontally and vertically oriented profiles are used, which are typically welded together. These profiles are designed to meet the locally required strength requirements and usually include one or more enclosed profile chambers. Longitudinal beams, also made of extruded lightweight metal profiles, are typically arranged at the transition points between the underframe and the side walls, and between the roof and the side walls. These beams are dimensioned to ensure optimal force transmission between the aforementioned large components.However, passenger rail vehicles, especially those used for local transport such as subways, have multiple door openings on each side, which significantly weakens the car body's structural integrity. To compensate for this loss of strength and prevent stress concentrations at the door opening corners, various design measures are implemented. For example, the wall thickness of the extruded aluminum profiles can be increased, or reinforcing components can be welded into the door corners. Both measures have significant drawbacks. On the one hand, increasing the wall thickness of the extruded aluminum profiles also increases the vehicle's mass; on the other hand, it also increases strength in areas where it is not needed.Welding in reinforcement components is a time-consuming and expensive manufacturing step in vehicle production, and the production of these components, typically by milling but also as castings, is complex and expensive.

[0003] WO2017093297A1 describes a hollow chamber profile which consists of two extruded profiles inseparably connected along their respective longitudinal extent, and in which at least one of the extruded profiles has different strengths by means of milling along its longitudinal extent. Description of the invention

[0004] The invention is therefore based on the objective of providing a longitudinal beam for a railway vehicle car body which can be designed to meet locally required strengths, which has the lowest possible mass and which can be manufactured exclusively using integral construction methods.

[0005] The problem is solved by a longitudinal beam for a rail vehicle with the features of claim 1. Advantageous embodiments are the subject of dependent claims.

[0006] According to the basic idea of ​​the invention, a longitudinal beam for a rail vehicle car body is described, which is divided into two partial beams along its longitudinal extent, wherein a first partial beam extends over the entire longitudinal extent, and wherein a second partial beam is divided into at least two longitudinal sections, each of which has different strength.

[0007] This offers the advantage of being able to provide a specific strength at certain longitudinal positions of the longitudinal beam.

[0008] According to the invention, a longitudinal beam is constructed from individual metal profiles, with a first profile (first partial beam) extending over the entire longitudinal dimension. At least two further profiles are arranged on this profile, and thus parallel to the first profile, and are firmly connected to the first profile. In this way, a longitudinal beam according to the invention is constructed from at least three metal profiles. The two further profiles, which each extend over a portion of the longitudinal dimension of the longitudinal beam, each have different strengths. Thus, a higher strength can be provided at certain positions, for example, at a connection point to a door pillar, than between these positions. This leads to a significant reduction in the mass of the entire longitudinal beam, since without the measure underlying the invention, the entire longitudinal beam would have to be designed with increased strength, even at positions where this is not necessary.

[0009] It is essential that a longitudinal beam according to the invention can be manufactured exclusively using the methods commonly employed in integral construction. Integral construction involves joining metal profiles (lightweight extruded metal profiles) by welding to form large components, which are in turn joined by welding to form a car body. Mechanical processing, typically milling of window openings, installation openings, etc., is also common. Further processing steps, such as welding in reinforcements (gusset plates) or inserting and welding reinforcing components, are labor-intensive, but these steps are unnecessary when using the present invention.

[0010] It is essential to provide a first sub-beam extending over the entire longitudinal dimension and to arrange further sub-beams on this first sub-beam, as this is the only way to prevent distortion of the entire longitudinal beam. If a longitudinal beam were assembled from individual longitudinal sections without this transverse division, the distortion caused by welding would be too great for further processing of the longitudinal beam.

[0011] The profiles of the individual sections of the second sub-beam have different strengths. Regardless of their strength, the profiles of the individual sections share the same outer contour, making them particularly easy to join together.

[0012] The different strengths of the individual profiles of the second sub-beam can be achieved in different ways, even with the same outer contour of the cross-section of the profiles.

[0013] On the one hand, the profiles can each have a different cross-section internally (varying wall thicknesses, additional webs, modified webs), or a different material can be used alternatively or additionally. In the latter case, weldability with the other profiles must be ensured. Brief description of the drawings

[0014] They show, for example: Fig. 1 Longitudinal beam, schematic diagram. Fig. 2 Side panel, schematic diagram. Fig. 3 Longitudinal beam, door column connection Fig. 4 First profile, cross-section Fig. 5 Second profile, cross-section. Fig. 6 Longitudinal beams. Implementation of the invention

[0015] Fig. 1This figure shows a highly abstracted schematic representation of a longitudinal beam. A longitudinal beam 1 consists of a first sub-beam 2 and a second sub-beam 3. The first sub-beam 2 is represented as a metal profile with a U-shaped cross-section, as is the second sub-beam 3. The second sub-beam 3 is divided into two longitudinal sections, with a first section 4 and a second section 5 joined end-to-end. Sections 4 and 5, along with the first sub-beam 2, are designed to be joined by welding in the position shown. The different strengths of sections 4 and 5 are not explicitly depicted in this schematic representation.

[0016] Fig. 2Figure 1 shows a schematic representation of a side wall with two longitudinal beams. It depicts a side wall of a passenger rail vehicle, constructed using an integral design from multiple extruded light alloy profiles. The side wall consists of several side wall profiles 6, arranged between a longitudinal beam 1 located at the top (roof side) and a longitudinal beam 1 located at the bottom (underframe side). A doorway is provided in the center of the side wall, bordered on both sides by door pillars 7. Each longitudinal beam 1 comprises a first sub-beam 2 extending over the entire length of the side wall and a second sub-beam 3 constructed from multiple sections.The second partial beam 3 is constructed from reinforced second sections 5 at the positions where the door columns 7 are attached; in between, the second partial beam 3 is constructed from first, unreinforced sections 4.

[0017] Fig. 3 Figure 1 shows an exemplary and schematic representation of a longitudinal beam at the position of a door column connection. The figure 1 is depicted, which is composed of a first sub-beam 2 and a second sub-beam 3. The second sub-beam 3 is divided into first sections 4 and a second section 5, with these sections 4 and 5 being connected to each other and to the first sub-beam 2 by means of a welded connection. The second section 5 is reinforced compared to the first section 4 and, in the illustrated embodiment, serves as the connection point to a door column. Fig. 3The image shows a machined longitudinal beam on which milling work has already been carried out after sections 4, 5 and the first partial beam 2 have been joined. The second section 5 has been machined to form a door corner, and the first section 4 on the right within the door opening has also been machined.

[0018] Fig. 4 shows, by way of example and schematically, the cross-section of a light metal extrusion profile, which is used as the first section 4 in the longitudinal beam 1 made of Fig. 3 The profile is designed as a multi-chambered, closed hollow profile, in which the chambers are stiffened by diagonally arranged webs. Furthermore, a C-rail is formed, to which additional components can be attached using T-nuts. Recesses extend downwards, suitable for connecting side panels.

[0019] Fig. 5shows, by way of example and schematically, the cross-section of a light metal extrusion profile, which is used as the second section 5 in the longitudinal beam 1 made of Fig. 3 This profile has the same outer contour as the one in Fig. 4 The profile shown in section 4 is used, but it is reinforced. The wall thickness at the connection point to a door jamb is significantly greater; however, the recesses for attaching side panels have been omitted, as these are not required at the door jamb positions.

[0020] Fig. 6Figure 1 shows an exemplary and schematic representation of a longitudinal beam. A longer section of a longitudinal beam 1 is depicted, as it is used above a doorway as a so-called roof longitudinal beam at the junction between a side wall and a roof. It is evident that the first sub-beam 2 is also designed as a closed, multi-chambered, lightweight metal extrusion. The cross-section of the first section 4 corresponds to that shown in Figure 1. Fig. 4 The reinforced second sections 5 are shown in the illustrated embodiment only at the connection points for door pillars, but it would also be possible to extend them over the entire door opening. Fig. 6 shows the longitudinal beam 1 in already completed machining steps; the connection of the components of the first partial beam 2 and sections 4, 5 takes place before this machining. List of designations

[0021] 1 Longitudinal beam 2 First partial beam 3 Second partial beam 4 First section 5 Second section 6 Side wall profile 7 Door pillar

Claims

1. Longitudinal beam (1) for a rail vehicle car body, which is divided into two sub-beams (2, 3) along its longitudinal extent, which sub-beams are embodied as light metal extruded profiles in each case, wherein a first sub-beam (2) extends as a first profile over the entire longitudinal extent, characterised in that a second sub-beam (3) is subdivided into at least two longitudinal sections (4, 5), which are arranged as two further profiles parallel to the first profile, and which have the same outer contour of their cross section but different strength in each case, wherein the longitudinal beam (1) is joined from the sub-beams (2, 3) by means of a welding process.

2. Longitudinal beam (1) for a rail vehicle car body according to claim 1, characterised in that the at least two longitudinal sections (4, 5) of the second sub-beam (3) have a different cross section in each case.

3. Longitudinal beam (1) for a rail vehicle car body according to one of claims 1 or 2, characterised in that the at least two longitudinal sections (4, 5) of the second sub-beam (3) are manufactured from a different material in each case.

4. Rail vehicle car body, comprising at least one longitudinal beam (1) according to one of claims 1 to 3, characterised in that sections with increased strength of the second sub-beam (3) are arranged at connection points with door pillars.