CN108657211B - Underframe for a rail vehicle and rail vehicle - Google Patents

Abstract

The application discloses a chassis for a rail vehicle and the rail vehicle, the rail vehicle is provided with a coupler, the chassis comprises: the two bogie installation seats are arranged at two ends of the length direction of the floor assembly, each bogie installation seat comprises an installation seat body, an inner cross beam and an outer cross beam, the inner cross beams and the outer cross beams are arranged at two ends of the installation seat body along the length direction of the floor assembly at intervals, the inner cross beams are connected with the floor assembly, the coupler is connected with the outer side wall of at least one outer cross beam, and the thickness of the outer side wall of the outer cross beam is larger than that of the inner side wall of the outer cross beam. According to the chassis for the railway vehicle, disclosed by the embodiment of the application, the assembly process of the coupler and the chassis is simplified, the overall weight of the chassis is reduced, a large amount of manpower and material resources are saved, the overall cost of the chassis is reduced, meanwhile, the structural strength of the outer cross beam is effectively ensured, and the safety and reliability of the chassis are ensured.

Description

Underframe for a rail vehicle and rail vehicle

Technical Field

The application relates to the technical field of railway vehicles, in particular to an underframe for a railway vehicle and the railway vehicle.

Background

In the related art, a coupler of a railway vehicle is usually fixed at the bottom of a chassis, which requires welding a plurality of bearing members under the chassis of the railway vehicle, increasing the weight of the chassis and making the assembly inconvenient.

Disclosure of Invention

The present application aims to solve at least one of the technical problems existing in the prior art. For this purpose, the application proposes a chassis for a rail vehicle, which is simple in structure, lightweight and easy to assemble.

Another object of the application is to propose a railway vehicle with an underframe as described above.

An undercarriage for a rail vehicle having a coupler according to an embodiment of the first aspect of the present application includes: a floor assembly; the two bogie mountings are arranged at two ends of the length direction of the floor assembly, each bogie mounting comprises a mounting seat body, an inner cross beam and an outer cross beam, the inner cross beams and the outer cross beams are arranged at two ends of the mounting seat body at intervals along the length direction of the floor assembly, the inner cross beams are connected with the floor assembly, the coupler is connected with at least one outer side wall of the outer cross beam, and the thickness of the outer side wall of the outer cross beam is larger than that of the inner side wall of the outer cross beam.

According to the chassis for the railway vehicle, the coupler is fixed on the outer cross beam of the bogie mounting seat, and the thickness of the outer side wall of the outer cross beam connected with the coupler is larger than that of the inner side wall, so that the assembly process of the coupler and the chassis is simplified, the overall weight of the chassis is reduced, a large amount of manpower and material resources are saved, the overall cost of the chassis is reduced, meanwhile, the structural strength of the outer cross beam is effectively ensured, and the safety and reliability of the chassis are ensured.

According to some embodiments of the application, the thickness of the outer sidewall is T, the thickness of the inner sidewall is T, and the T, T satisfies: T-T is more than or equal to 5mm.

Specifically, the thickness T of the outer sidewall satisfies: t is more than or equal to 25mm and less than or equal to 30mm.

According to some embodiments of the application, the chassis further comprises: the two side beams are arranged at two ends of the underframe at intervals along the width direction of the floor assembly, a first lap joint part is arranged on one side, adjacent to the floor assembly, of the side beams, the first lap joint part comprises a first main body part and a first lap joint beam, the first main body part is connected with the side wall of the side beams, the first lap joint beam is connected with the bottom of the first main body part and extends towards the floor assembly, a second lap joint part is arranged on one side, adjacent to the side beams, of the floor assembly, the second lap joint part comprises a second main body part and a second lap joint beam, the second main body part is connected with the side wall of the floor assembly, the second lap joint beam is connected with the top of the second main body part and extends towards the side beams, the second main body part is suitable for being lapped on the first lap joint beam, and the second lap joint beam is suitable for being lapped on the first main body part.

Specifically, the first main body part forms to hollow structure, the roof of first main body part includes first section, second section and changeover portion, first section with the lateral wall of boundary beam links to each other and the upper surface of first section with the upper surface parallel and level of the roof of boundary beam, the changeover portion one end with first section links to each other, the other end with the second section links to each other, in being close to in the direction of floor assembly, the changeover portion downward sloping extends.

According to some embodiments of the application, the side rail is formed as a hollow structure, a first reinforcing rib is provided in the side rail, the first reinforcing rib includes a first sub rib connected to an upper end of the side wall of the side rail and a second sub rib connected to a lower end of the side wall of the side rail, and the first sub rib and the second sub rib extend toward each other in a direction away from the floor assembly.

Optionally, the thickness of the top wall of the side rail is smaller than the thickness of the bottom wall thereof.

According to a further embodiment of the application, at least one first C-shaped groove is provided on the top wall and the bottom wall of the side rail, respectively.

According to some embodiments of the application, a third lap joint part suitable for lap joint with the side wall of the railway vehicle is arranged on the top wall of the side beam, the third lap joint part is positioned at one end of the side beam far away from the first lap joint part, a second reinforcing rib is arranged in the third lap joint part, and the second reinforcing rib and the side wall of the third lap joint part far away from the floor assembly enclose a graph with a triangular cross section.

Specifically, at least one second C-shaped groove is respectively arranged on the upper surface and the lower surface of the floor assembly.

Optionally, the chassis is an aluminum alloy piece.

A rail vehicle according to an embodiment of the second aspect of the application comprises a chassis for a rail vehicle according to the embodiment of the first aspect of the application described above.

According to the rail vehicle of the second aspect of the embodiment of the application, by arranging the underframe for the rail vehicle according to the first aspect of the embodiment of the application, the overall performance of the rail vehicle is improved.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Drawings

The foregoing and/or additional aspects and advantages of the application will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 is a top view of a chassis according to an embodiment of the present application;

FIG. 2 is a top view of a chassis according to another embodiment of the present application;

FIG. 3 is a schematic view of the structure of an outer cross member according to an embodiment of the present application;

FIG. 4 is a cross-sectional view of an outer cross-beam according to an embodiment of the application;

FIG. 5 is a schematic illustration of the assembly of a floor assembly with side rails according to an embodiment of the application;

FIG. 6 is a cross-sectional view of a side rail according to an embodiment of the present application;

FIG. 7 is a cross-sectional view of a floor assembly according to an embodiment of the application.

Reference numerals:

the chassis 100 is configured such that,

floor assembly 1, floor 11, w-shaped stiffener 112, second C-shaped groove 113,

a second overlap 12, a second body 121, a second overlap beam 122,

the bogie mounting seat 2, the mounting seat body 21, the mounting portion 211,

the inner cross member 22,

the outer cross member 23, outer side wall 231, inner side wall 232, screw hole 233,

the side sill 3, the first lap portion 31, the first body portion 311, the first lap beam 312,

the first segment 3131, the second segment 3132, the transition segment 3133,

the first reinforcing rib 32, the first sub-rib 321, the second sub-rib 322,

the square-shaped reinforcing rib structure 33,

the first C-shaped slot 34 is provided,

and a third lap joint portion 35, a second reinforcing rib 351.

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the application.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element in question must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, features defining "first", "second" may include one or more such features, either explicitly or implicitly. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

An undercarriage 100 for a rail vehicle according to an embodiment of the first aspect of the present application is described below with reference to fig. 1-7. The rail vehicle may be a light rail vehicle or the like. The chassis 100 may be an intermediate chassis (as shown in fig. 1) or a headstock chassis (as shown in fig. 2).

As shown in fig. 1 and 2, a chassis 100 for a railway vehicle according to an embodiment of the present application includes: a floor assembly 1 and two truck mounts 2. Two truck mounts 2 are provided at both ends in the longitudinal direction (e.g., the front-rear direction in fig. 1) of the floor assembly 1. For convenience of description, in the following description of the present application, the bogie mount 2 at the front end of the floor assembly 1 is referred to as a "front bogie mount", and the bogie mount 2 at the rear end of the floor assembly 1 is referred to as a "rear bogie mount".

Each bogie mounting seat 2 comprises a mounting seat body 21, an inner cross beam 22 and an outer cross beam 23, wherein the inner cross beam 22 and the outer cross beam 23 are arranged at two ends of the mounting seat body 21 along the length direction of the floor assembly 1 at intervals, the inner cross beam 22 is connected with the floor assembly 1, the railway vehicle is provided with a coupler which is connected with the outer side wall 231 of at least one outer cross beam 23, and the thickness of the outer side wall 231 of the outer cross beam 23 is larger than that of the inner side wall 232 of the outer cross beam 23.

That is, the coupler may be connected to the outer side wall 231 of the outer beam 23 of one of the truck mounts 2, or may be connected to the outer side walls 231 of the outer beams 23 of both truck mounts 2, respectively. Wherein the thickness of the outer side wall 231 of the outer beam 23 connected to the coupler is greater than the thickness of the inner side wall 232 thereof. In the process of acceleration and deceleration of the railway vehicle, the joint of the outer cross beam 23 and the coupler is required to bear larger force, the inner side wall 232 of the outer cross beam 23 is connected with the bogie mounting seat 2, and the resistance is smaller. The thickness of the outer side wall 231 of the outer cross beam 23 connected with the coupler is set to be larger than that of the inner side wall 232 of the outer cross beam, so that the structural strength of the outer cross beam 23 can be ensured, the safety and reliability of the underframe 100 are further ensured, materials can be reduced, and the overall installation cost and weight of the underframe 100 are reduced.

Specifically, when the undercarriage 100 is a center car undercarriage (as shown in fig. 1), the couplers may be connected to the outer cross member 23 of the front and rear truck mounts 2, 23, respectively, each having a thickness greater than a thickness of the inner side wall 232 thereof. When the undercarriage 100 is a headstock undercarriage (as shown in fig. 2), the coupler may be connected to the outer sidewall 231 of the rear truck mount, the thickness of the outer beam 23 of the rear truck mount may be greater than the thickness of the inner sidewall 232 thereof, and the thicknesses of the outer sidewall 231 and the inner sidewall 232 of the outer beam 23 of the front truck mount may not be required.

Specifically, the outer beam 23 connected to the coupler may be provided with screw holes 233, for example, in the example of fig. 3, four screw holes 233 are provided on the outer beam 23, the screw holes 233 may be located in the middle of the outer beam 23, and bolts sequentially pass through the coupler and the screw holes 233 on the outer beam 23 to fix the coupler to the outer beam 23. The novel chassis 100 is simple in structure and convenient to assemble, a carrier for fixing the coupler is not required to be additionally welded on the chassis 100, the overall weight of the chassis 100 is reduced, the assembly process of the coupler and the chassis 100 is simplified, a large amount of manpower and material resources are saved, and the overall cost of the chassis 100 is reduced.

Here, it should be noted that the term "middle portion of the outer cross member 23" in the present application should be interpreted broadly, that is, the middle portion in a strict sense is not required. In addition, in the description of the present application, the term "outer" refers to a side away from the center of the chassis 100, and correspondingly, the term "inner" refers to a side adjacent to the center of the chassis 100. For example, the "outer beam 23" in the present application refers to a beam that is far from the center of the chassis 100, and correspondingly, the "inner beam 22" refers to a beam that is near the center of the chassis 100. As another example, "inner sidewall 232" refers to a sidewall adjacent to the center of the chassis 100, and "outer sidewall 231" refers to a sidewall remote from the center of the chassis 100.

According to the chassis 100 for the railway vehicle, according to the embodiment of the application, the coupler is fixed on the outer beam 23 of the bogie installation seat 2, and the thickness of the outer side wall 231 of the outer beam 23 connected with the coupler is larger than that of the inner side wall 232 of the outer beam, so that the assembly process of the coupler and the chassis 100 is simplified, the overall weight of the chassis 100 is lightened, a large amount of manpower and material resources are saved, the overall cost of the chassis 100 is reduced, the structural strength of the outer beam 23 is effectively ensured, and the safety and reliability of the chassis 100 are ensured.

According to some embodiments of the application, the thickness T of the outer sidewall 231 and the thickness T, T, T of the inner sidewall 232 satisfy: T-T is more than or equal to 5mm. Specifically, the thickness T of the outer side wall 231 and the thickness T of the inner side wall 232 of the outer cross member 23 connected to the coupler may satisfy: T-T is more than or equal to 5mm. For example, in some embodiments of the present application, the thickness T of the outer sidewall 231 may satisfy: t is more than or equal to 25mm and less than or equal to 30mm. Alternatively, the thickness T of the outer sidewall 231 may satisfy: t=25 mm, t=27 mm, t=30 mm, etc. Therefore, the overall structural strength of the outer cross beam 23 can be effectively ensured, the safety and reliability of the underframe 100 and the railway vehicle are ensured, materials can be saved, the overall weight of the underframe 100 is reduced, and the material cost is reduced.

In particular, the inner side wall 232 of the outer cross member 23 may overlap the bogie mounting seat 2, thereby facilitating welding, assembling, and securing sufficient strength.

Specifically, referring to fig. 7, the floor assembly 1 includes a plurality of (e.g., five, etc.) floors 11 sequentially connected along a width direction (e.g., a left-right direction in fig. 1) of the chassis 100, the floors 11 are of an extruded profile structure, groove insertion portions are provided on the floors 11, and two adjacent floors 11 are inserted and welded first, thereby facilitating connection between the floors 11, and simultaneously ensuring that the two adjacent floors 11 are fused when the profiles of the two adjacent floors 11 are welded, so as to facilitate increasing thickness and strength of a welding seam, and thereby enabling connection between the two adjacent floors 11 to be more firm and reliable.

According to some embodiments of the present application, referring to fig. 7, the floor 11 is internally provided with W-shaped reinforcing ribs 112. This structure ensures structural strength of the floor panel 11 while reducing the weight of the floor panel 11, and has high strength when the floor panel 11 is subjected to both longitudinal load and lateral load.

Further, at least one second C-shaped groove 113 is provided on the upper and lower surfaces of the floor assembly 1, respectively. Wherein the second C-shaped groove 113 may be one or more. For example, in the example of fig. 7, two second C-shaped grooves 113 are provided on the upper and lower surfaces of each floor panel 11, respectively, and the second C-shaped grooves 113 on the upper surface of the floor panel 11 and the second C-shaped grooves 113 on the lower surface of the floor panel 11 are staggered with each other. The second C-shaped groove 113 may provide a mounting point for the under-vehicle electrical equipment, the in-vehicle equipment, and the interior floor 11.

According to some embodiments of the application, the chassis 100 further comprises: two side sills 3, the two side sills 3 being provided at both ends of the bottom chassis 100 at intervals in the width direction (e.g., left-right direction in fig. 1) of the floor assembly 1. Specifically, each side rail 3 extends from the front end of the chassis 100 to the rear end of the chassis 100.

When the underframe 100 is a headstock underframe, the boundary beam 3 at the front bogie mounting seat of the headstock underframe is formed into an arc shape to adapt to the headstock modeling. Wherein the arc length is L, and L is more than or equal to 3m. The chassis 100 may be simplified in construction due to the greater arc and lighter load.

The side of the side sill 3 adjacent to the floor assembly 1 is provided with a first overlap portion 31, the first overlap portion 31 includes a first main body portion 311 and a first overlap beam 312, the first main body portion 311 is connected to the side wall of the side sill 3, and the first overlap beam 312 is connected to the bottom of the first main body portion 311 and extends toward the floor assembly 1. For example, the right side wall of the left side sill 3 of the chassis 100 is provided with a first lap joint 31, and the left side wall of the right side sill 3 of the chassis 100 is provided with a first lap joint 31. The side of the floor assembly 1 adjacent to the side rail 3 is provided with a second overlap portion 12, the second overlap portion 12 comprises a second body portion 121 and a second overlap beam 122, the second body portion 121 is connected to the side wall of the floor assembly 1, the second overlap beam 122 is connected to the top of the second body portion 121 and extends towards the side rail 3, the second body portion 121 is adapted to overlap the first overlap beam 312, and the second overlap beam 122 is adapted to overlap the first body portion 311.

Referring to fig. 7, the floor assembly 11 is provided at both left and right ends thereof with a second overlap portion 12, respectively. Referring to fig. 5-7, the first body portion 311 and the second body portion 121 are formed into a generally hollow square structure, the first bridging beam 312 is generally parallel to the floor assembly 1, and the second bridging beam 122 may be formed as an extension plate of the upper panel of the floor assembly 1.

Because the right floor 11 of the floor assembly 1 is formed by assembling and welding, the length is large, the welding lines are more, welding deformation can be inevitably generated in the welding process, the first lap joint part 31 is arranged on the side beam 3, and the second lap joint part 12 is arranged on the floor assembly 1, so that the second main body part 121 of the second lap joint part 12 is lapped on the first lap joint part 312 of the first lap joint part 31, and the second lap joint part 122 of the second lap joint part 12 is lapped on the first main body part 311 of the first lap joint part 31, the contact area between the floor assembly 1 and the side beam 3 is increased, the dimensional error caused by the welding deformation is effectively solved, and meanwhile, the welding between the floor assembly 1 and the side beam 3 is convenient.

Specifically, the first body portion 311 is formed in a hollow structure, and the top wall of the first body portion 311 includes a first segment 3131, a second segment 3132, and a transition segment 3133, the first segment 3131 being connected to the above-described side wall of the side sill 3 and the upper surface of the first segment 3131 being flush with the upper surface of the top wall of the side sill 3, one end of the transition segment 3133 being connected to the first segment 3131, the other end being connected to the second segment 3132, the transition segment 3133 extending obliquely downward in a direction approaching the floor assembly 1. Thereby facilitating the overlapping of the second overlapping beam 122 over the first body portion 311.

According to some embodiments of the present application, the side sill 3 is formed in a hollow structure, the side sill 3 is provided therein with a first reinforcing rib 32, the first reinforcing rib 32 includes a first sub-rib 321 and a second sub-rib 322, the first sub-rib 321 is connected to an upper end of the side wall of the side sill 3, the second sub-rib 322 is connected to a lower end of the side wall of the side sill 3, and the first sub-rib 321 and the second sub-rib 322 extend toward each other in a direction away from the floor assembly 1. Referring to fig. 6, the side sill 3 may be internally provided with two upper and lower rows of square reinforcing rib structures 33, the first sub-ribs 321 may extend along the diagonal of the upper row of square reinforcing ribs, and the second sub-ribs 322 may extend along the diagonal of the lower row of square reinforcing ribs. The first sub-bead 321 intersects the second sub-bead 322. Thereby, the structural strength of the side sill 3 can be effectively improved, the bearing load of the side sill 3 is increased, and the safety and reliability of the underframe 100 and the railway vehicle are improved.

Optionally, the thickness of the top wall of the side rail 3 is smaller than the thickness of the bottom wall thereof. Because the roof of boundary beam 3 bears the weight of less than its diapire and bears the weight of, set up the thickness of boundary beam 3 roof to be less than the thickness of diapire, that is to say, set up the thickness of diapire bigger, from this, can guarantee the overall structure intensity of boundary beam 3 and can reduce the materials of boundary beam 3, reduce material cost.

According to a further embodiment of the application, the side rail 3 is provided with at least one first C-shaped groove 34 on the top and bottom wall, respectively. Wherein the top and bottom walls of the side rail 3 may be provided with one or more first C-shaped grooves 34, respectively. Wherein, the first C-shaped groove 34 on the roof of the boundary beam 3 can provide a mounting point for the fixed interior aluminum honeycomb floor 11, and the first C-shaped groove 34 on the bottom wall of the boundary beam 3 can provide a mounting point for the apron hinge.

According to some embodiments of the present application, a third overlap portion 35 adapted to overlap with a side wall of the rail vehicle is provided on a top wall of the side sill 3, the third overlap portion 35 is located at an end (e.g., a right end in fig. 6) of the side sill 3 away from the first overlap portion 31, a second reinforcing rib 351 is provided in the third overlap portion 35, and the second reinforcing rib 351 and a side wall of the third overlap portion 35 away from the floor assembly 1 enclose a graph having a triangular cross section. Therefore, the structural strength of the boundary beam 3 is improved, the boundary beam 3 can bear larger transverse force, the overlap joint between the underframe 100 and the side wall of the railway vehicle is firmer, and the stability of the side wall and the vehicle body of the railway vehicle is improved.

Alternatively, the chassis 100 is an aluminum alloy member. Specifically, the chassis 100 may be an aluminum alloy extrusion profile, and thus, the weight of the chassis 100 may be reduced, and energy consumption may be reduced.

According to some embodiments of the application, a traction mechanism (not shown) of a rail vehicle may be mounted on the bogie mount 2. Wherein, the traction mechanism has three traction points. The three traction points are arranged in sequence along the width direction of the floor assembly 1. When the vehicle body turns or receives lateral force, the traction point in the middle can share the lateral force, so that the relative displacement between the bogie mounting seat 2 and the vehicle body is reduced; the stability of the vehicle body is increased, the turning radius of the vehicle can be reduced, and the vehicle can be more suitable for complex urban air traffic conditions.

According to some embodiments of the present application, the mounting base body 21 is formed by splicing a plurality of bogie mounting profiles, the mounting base body 21 has a through mounting portion 211 therein, and the tire of the railway vehicle is located half below the underframe 100 and half above the underframe 100. Therefore, the height of the whole vehicle body can be reduced, the gravity center of the whole vehicle is reduced, and the stability of the vehicle body is improved.

The rail vehicle according to the embodiment of the second aspect of the present application comprises the chassis 100 for a rail vehicle according to the embodiment of the above-described first aspect of the present application.

According to the rail vehicle of the second aspect of the embodiment of the present application, by providing the underframe 100 for the rail vehicle according to the above-described first aspect of the embodiment of the present application, the overall performance of the rail vehicle is improved.

Other constructions and operations of rail vehicles according to embodiments of the present application are known to those of ordinary skill in the art and will not be described in detail herein.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the application, the scope of which is defined by the claims and their equivalents.

Claims (12)

1. A chassis for a rail vehicle, the rail vehicle having a coupler, the chassis comprising:

the floor assembly is formed by assembling and welding a plurality of floors;

the two bogie mountings are arranged at two ends of the length direction of the floor assembly, each bogie mounting comprises a mounting seat body, an inner cross beam and an outer cross beam, the inner cross beams and the outer cross beams are arranged at two ends of the mounting seat body at intervals along the length direction of the floor assembly, the inner cross beams are connected with the floor assembly, the coupler is connected with at least one outer side wall of the outer cross beam, and the thickness of the outer side wall of the outer cross beam is larger than that of the inner side wall of the outer cross beam.

2. The undercarriage for a rail vehicle of claim 1 wherein the outer sidewall has a thickness T and the inner sidewall has a thickness T, the T, T satisfying: T-T is more than or equal to 5mm.

3. The undercarriage for a rail vehicle of claim 2 wherein the thickness T of the outer sidewall satisfies: t is more than or equal to 25mm and less than or equal to 30mm.

4. The undercarriage for a rail vehicle of claim 1 further comprising:

the two side beams are arranged at two ends of the underframe at intervals along the width direction of the floor assembly, one side of the side beam adjacent to the floor assembly is provided with a first lap joint part, the first lap joint part comprises a first main body part and a first lap joint beam, the first main body part is connected with the side wall of the side beam, the first lap joint beam is connected with the bottom of the first main body part and extends towards the floor assembly,

the floor assembly is characterized in that a second lap joint part is arranged on one side, adjacent to the side beam, of the floor assembly, the second lap joint part comprises a second main body part and a second lap joint beam, the second main body part is connected with the side wall of the floor assembly, the second lap joint beam is connected with the top of the second main body part and extends towards the side beam, the second main body part is suitable for being lapped on the first lap joint beam, and the second lap joint beam is suitable for being lapped on the first main body part.

5. The undercarriage for a rail vehicle of claim 4 wherein the first body portion is formed as a hollow structure, the top wall of the first body portion includes a first section, a second section, and a transition section, the first section is connected to the side wall of the side sill and the upper surface of the first section is flush with the upper surface of the top wall of the side sill, one end of the transition section is connected to the first section, the other end is connected to the second section, and the transition section extends obliquely downward in a direction approaching the floor assembly.

6. The undercarriage for a railway vehicle according to claim 4, wherein the side sill is formed in a hollow structure, a first reinforcing rib is provided in the side sill, the first reinforcing rib includes a first sub rib connected to an upper end of the side wall of the side sill, and a second sub rib connected to a lower end of the side wall of the side sill, and the first sub rib and the second sub rib extend toward each other in a direction away from the floor assembly.

7. The undercarriage for a rail vehicle of claim 4 wherein the top wall of the side rail has a thickness that is less than the thickness of the bottom wall thereof.

8. The undercarriage for a rail vehicle of claim 4 wherein the side rail has at least one first C-shaped groove formed in each of the top and bottom walls.

9. The underframe for a railway vehicle as claimed in claim 4, wherein a third lap joint part which is suitable for lap joint with a side wall of the railway vehicle is arranged on the top wall of the side beam, the third lap joint part is positioned at one end of the side beam far away from the first lap joint part, a second reinforcing rib is arranged in the third lap joint part, and a graph with a triangular cross section is formed by the second reinforcing rib and a side wall of the third lap joint part far away from the floor assembly.

10. The undercarriage for a rail vehicle of claim 1 wherein the floor assembly has at least one second C-shaped groove on each of the upper and lower surfaces.

11. The undercarriage for a rail vehicle of any one of claims 1-10 wherein the undercarriage is an aluminum alloy member.

12. Rail vehicle, characterized in that it comprises a chassis for a rail vehicle according to any of claims 1-11.