EP3643577B1 - Casing structure for a vehicle box and method for the preparation of same - Google Patents

Description

The invention relates to an enveloping structure for a car body for a vehicle, and to a method for producing an enveloping structure.

Shell structures of car bodies are often formed from double-layer structures such as double-walled aluminum extrusions. In the case of aluminum car bodies, the double-walled structure ensures sufficient strength and low weight at the same time. For this purpose, the outer and inner walls of the extruded aluminum profiles are usually connected to one another via struts, which transmit the forces introduced into the enveloping structure or distribute them to the outer and inner walls.

The extruded profiles are produced in the required length in an extrusion process and then placed on top of one another and welded together to produce the enveloping structure, i.e. the car body floors, walls and ceilings. Due to the double-walled design of the extruded aluminum profiles, it is necessary for both the outer and inner walls of the extruded profiles placed on top of each other to be connected to one another in a force-conducting manner. This usually takes place via weld seams, which have to be applied both to the outside and to the inside of the car body during manufacture of the car body.

A problem in the production of car bodies using welds on both sides is the limited space available in the interior of the car body, which makes automated production of the welds by welding robots more difficult. In addition, the welding process that takes place from the inside makes it difficult or prevents possible pre-assembly of components on the enveloping structure elements, on the one hand because of the space required for welding and on the other hand because of the heat input caused by welding, which can damage these components.

In the state of the art, solutions are proposed which allow the structural envelope elements to be welded exclusively from the outside.

the DE 10 2007 048 759 A1 and the US 2003/0042293 A1 disclose a method for manufacturing a car body, in which two enveloping structural elements positioned relative to one another in an assembly position together form an access opening through which the inner walls of the enveloping structural elements can be welded to one another from outside the car body. After this Welding the inner walls closes this access opening with a metallic cover. The cover is then welded to the two skin structural elements and forms part of the structure of the skin of the car body.

A similar procedure is shown in EP 3 272 616 A1 . A metallic structural member is first inserted into the access opening and welded to the adjacent enveloping structural members to provide structural strength. The weld seams are at a distance from the actual edge of the access opening, so that the heat input at the edge of the access opening remains low. Consequently, the enveloping structure elements can be varnished before the welding process without the varnish layer being damaged during the subsequent welding process. The access opening is then closed by a cover which is adhesively bonded to the shell structure elements. The technical environment will continue to the JP 2001 038478 A referred.

A disadvantage of the known solutions for producing an enveloping structure is the effort required. Additional components must be provided and welded to the skin structure to provide the space required for the inner wall weld.

The invention is therefore based on the object of providing an enveloping structure for a car body that is simple and inexpensive to produce.

According to the invention, this object is achieved with an enveloping structure according to claim 1 . Furthermore, the object is achieved with a method for producing an enveloping structure according to claim 15. Advantageous developments of the invention are contained in the dependent claims.

According to the invention, the solution to the problem for an enveloping structure is that the first enveloping structure element is provided with an extension that extends between the outer wall and the inner wall in an insertion direction, and the second enveloping structure element is provided with a receptacle that opens between the outer wall and the inner wall counter to the insertion direction Insertion of the extension. The extension includes a form-fitting means and the receptacle is filled with a filling material. The extension accommodated in the receptacle and the filling material surrounding the form-fitting means at least in sections thus produce a form-fitting connection. In addition, the first shell structure element and the second shell structure element are connected to one another by a weld seam.

Because a second form-fitting connection, acting parallel to the weld seam, is produced between the first and second enveloping structure element via the form-fitting means next to the weld seam, only one weld seam and only one welding process is required. A second weld seam can be dispensed with. The welding process can take place from only one side of the enveloping structure, in particular from the outside.

For good power transmission between the enveloping structure elements or for the best possible transmission of bending moments that occur, the weld seam and the form-fitting connection are preferably arranged at a great distance from one another and/or on opposite sides of a central plane of the enveloping structure. The form-fitting connection is preferably arranged close to an edge region of the enveloping structure, in particular on an outside of the enveloping structure, which faces outwards when the car body is installed.

In the method according to the invention for producing an enveloping structure for a car body, after the provision of a first and a second enveloping structure element, the extension of the first enveloping structure element is first inserted into the receptacle of the second enveloping structure element. The receptacle of the second enveloping structure element is then filled with a filling material that hardens in particular at low temperatures or cold. In addition, the first structural envelope element is welded to the second structural envelope element on one side, i.e. from one side. Only one weld seam is preferably produced.

Welding of the structural shell elements can take place before or after the filling of the receptacle, with welding of the structural shell elements after the receptacle has been filled and the filling material has hardened being preferred because the structural shell elements are thus already fixed in their final position during the welding process. The hardened filling material finally forms a form fit with the form fit means located on the extension.

The enveloping structure according to the invention can be suitable for a car body of a railway vehicle, or for other vehicles such as buses.

The extension can have an indentation which extends essentially perpendicularly to the direction of insertion and which forms the form-fitting means. Alternatively or additionally, the form-fitting means can be formed by an elevation or a through-opening.

The extension can have an undercut into which the filling material can flow. After the extension has been inserted into the receptacle, the filling material can be conveyed into the receptacle under pressure in order to ensure that the filling material completely surrounds or borders the form-fitting means.

Furthermore, the filling material can also form a form fit with the receptacle. The receptacle can have a receptacle opening for inserting the extension. The receptacle preferably widens in the insertion direction, starting from the receptacle opening, or the receptacle tapers in the opposite direction to the insertion direction. A filling material that has been poured into the receptacle and has hardened cannot be pushed out through the receptacle opening and forms a form fit with the receptacle.

According to an expedient variant of the invention, at least one inner wall of the receptacle can be at a distance from the extension or the form-fitting means. The distance ensures that the filling material completely surrounds the form-fitting means and forms an effective form-fitting connection with it. Ideally, the form-fitting means is at a distance from the inner wall or walls of the receptacle over its entire circumference.

In a preferred embodiment of the enveloping structure, the receptacle is designed in such a way that the filling material can be conveyed into the receptacle under pressure. The second enveloping structure element can be provided with a filling opening which penetrates through the outer wall or inner wall of the second enveloping structure element and leads into the receptacle. In order to be able to fill the receptacle evenly and completely in the case of longer enveloping structure elements, several filling openings can be provided. The filling openings can preferably be arranged in a transverse direction of the enveloping structure element at the same height as the form-fitting means.

For easy assembly of the enveloping structure, the insertion direction in which the extension is inserted into the receptacle runs essentially parallel to the outer wall and/or to the inner wall of the first enveloping structure element.

Ideally, the extension is accommodated in the receptacle when the outer walls and/or inner walls of the enveloping structure elements are aligned with one another. The extension can thus be introduced into the receptacle or positioned in the receptacle by aligning the outer and/or inner walls.

In order to predominantly compress the filling material in the hardened state and to reduce tensile and shearing forces, the receptacle can widen conically or funnel-shaped starting from the receptacle opening. The receptacle acts as a mold for the filling material. The filling material can thus form a filling body that is conical at least in sections in the hardened state. A tensile force acting on the extension or the form-fitting means can thus continue via the conical surface of the filling body as a compressive force on the inner surface of the receptacle, which is also conical.

Alternatively or additionally, the filling material can be adhesively bonded to the extension and/or the receptacle. The adhesive connection can be made directly over the filling material, e.g. by using a curing adhesive as the filling material.

With the invention, only one weld seam is required to weld the enveloping structure on one side. The enveloping structure is preferably welded on the outside. The respective other side, preferably the inside of the enveloping structure, is positively connected via the extension in the first enveloping structure element, the receptacle in the second enveloping structure element and the filling material in the receptacle. In a transverse direction running transversely to the direction of insertion, the form fit can be produced at least partially via the extension and a receiving opening of the receptacle. The receiving opening, into which the extension can be inserted, can have a width that is only slightly larger than the extension, if possible, in order to enable the transmission of force with as little play as possible.

In a preferred embodiment of the invention, the weld seam can be arranged on mutually opposite surfaces of the inner wall or the outer wall of the first structural envelope element and the second structural envelope element. Opposite surfaces of the outer walls of the first and second shell structure element are preferably welded to one another, while opposite surfaces of the inner walls have no weld seams. In this way, the integral connection of the two enveloping structure elements can be produced solely from the outside. The weld seam can be applied to the enveloping structure from the outside in order to be able to provide sufficient space for welding devices or welding robots.

According to an expedient development of the invention, the first and/or second enveloping structure element are formed from extruded profiles, in particular aluminum extruded profiles. These can be produced efficiently, while high strength can be achieved with low weight.

In a preferred variant of the invention, the first structural shell element including the extension and/or the second structural shell element including the receptacle is formed from an extruded profile. Extension and/or receptacle can correspondingly extend over the entire length of the respective extruded profile. In order to also be able to produce the form-fitting means together with the enveloping structure element in the extrusion process, this is preferably designed as a solid profile.

In order to prevent an uncontrolled spread of the welding medium during welding, a weld pool safety device can be provided. The weld pool backup can preferably be formed by the first or second enveloping structure element and in particular can be part of an aluminum extruded profile. Thus, the first or the second enveloping structure element can have an extension which engages behind the weld seam from the inside and which is suitable for forming a weld pool backup. The extension can preferably overlap the parting line between two walls to be welded of the first and second enveloping structure element.

A material that hardens at low temperatures, e.g. at room temperature or cold, is preferably provided as the filling material. In a preferred embodiment of the invention, the filling material is liquid in a processing state at relatively low temperatures, in particular at temperatures below 300°C, preferably at temperatures below 200°C, most preferably at temperatures below 100°C. Alternatively, the filler material can be liquid in a processing state at temperatures below 40°C.

The filling material can be designed to have an adhesive effect in order to adhesively fasten the extension in the receptacle. The extension or the form-fitting means can be held in the receptacle in a form-fitting and adhesive manner. The filling material may comprise a cold-setting plastic such as a thermoset. In addition, fibers can be provided in the filling material in order to form a high-tensile fiber composite. Alternatively or additionally, a pressure-resistant component can be added, such as sand, in particular quartz sand, ceramic or metal, in order to increase the pressure resistance of the filling material. In order to ensure a seamless form fit, the filling material can have a component that expands during curing.

A rail vehicle according to the invention has one of the above-described embodiments of an enveloping structure according to the invention.

The accompanying drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. The following is with reference to the figures 1 and 2 a preferred embodiment of the enveloping structure according to the invention is described.

• Fig. 1 Eine geschnittene Darstellung eines Ausschnitts eines ersten Hüllstrukturelementes und eines zweiten Hüllstrukturelementes für eine Hüllstruktur;
• Fig. 2 Eine geschnittene Darstellung eines Ausschnitts einer Hüllstruktur eines Schienenfahrzeuges aus einem ersten und einem zweiten Hüllstrukturelement.

Show it:

• 1 A sectional representation of a section of a first enveloping structure element and a second enveloping structure element for an enveloping structure;
• 2 A sectional representation of a detail of an enveloping structure of a rail vehicle consisting of a first and a second enveloping structure element.

1 shows the essential components for an enveloping structure according to the invention, namely a first enveloping structure element 2 and a second enveloping structure element 3. Both the first enveloping structure element 2 and the second enveloping structure element 3 are double-walled. The first structural envelope element 2 has an outer wall 4 and an inner wall 5, the second structural envelope element 3 has an outer wall 6 and an inner wall 7. Outer walls 4, 6 and inner walls 5, 7 are connected to one another via struts 22, 23, which are connected between outer walls 4, 6 and inner walls 5, 7 transmitted forces occurring. The struts 22, 23 can form a framework structure between the outer and inner walls. You can run horizontally or diagonally in the further course of the shell structure elements 2, 3.

The first enveloping structure element 2 and the second enveloping structure element 3 are designed in such a way that they are placed on top of one another or plugged into one another in an assembly position and are aligned by guide surfaces.

For this purpose, an extension 8 is provided on the first structural envelope element 2 and a receptacle 9 on the second structural envelope element 3 . The receptacle 9 has a receptacle opening 16 through which the extension 8 can be inserted into the receptacle 9 . The extension 8 is part of the extruded profile from which the first structural envelope element 2 is formed and extends over the entire length of the structural envelope element 2. The receiving opening 16 is correspondingly part of the aluminum extruded profile, from which the second shell structure element 3 is formed, and extends over the entire length of the second shell structure element 3.

In order to enable the first enveloping structure element 2 to be guided in the second enveloping structure element 3, the width B of the receiving opening 16 is only slightly wider than the width b of the extension 8. The extension 8 therefore acts together with the accommodating opening 16 as a guide for the first enveloping structure element 2 in the second enveloping structure element 3, wherein the guide restricts the movement of the first enveloping structure element 2 relative to the second enveloping structure element 3 in a transverse direction Q. In a preferred embodiment, a clearance fit can be provided between the extension 8 and the receiving opening 16 .

The movement of the structural covering elements 2, 3 relative to one another is also limited in the insertion direction E. Support surfaces 17 are provided on the first structural envelope element 2 on both sides of the extension 8, and support surfaces 18 are provided on the second structural envelope element 3 on both sides of the receiving opening 16.

in the in 1 shown mounting position of the enveloping structure elements 2, 3, the outer walls 4, 6 and the inner walls 5, 7 are aligned with each other. The first structural envelope element 2 can now be moved onto the second structural envelope element 3 until the extension 8 reaches the receptacle 9 and the bearing surfaces 17 come to rest on the bearing surfaces 18 .

First and second shell structure element 2, 3 are designed to be welded together. For this purpose, a welding surface 19 for receiving a weld seam is arranged on the outer wall 4 of the first enveloping structure element 2, and a welding surface 20 is arranged on the second enveloping structure element 3. The welding surfaces 19 and 20 run at an angle to the outer walls 4, 6, so that when the enveloping structure elements 2, 3 an externally accessible depression for receiving the welding material is created.

The first enveloping structure element 2 also has a weld pool safety device 21, which is used to catch welding material escaping during the welding process. The weld pool backup 21 is part of the first enveloping structure element 2 and is produced with it in one operation using the extrusion process. The weld pool backup 21 extends in the direction of insertion E and, when the enveloping structure is assembled, overlaps the welding joint between the enveloping structure elements 2, 3. A support surface 12 provided on the weld pool backup 21 on the first enveloping structure element 2 is arranged opposite a support surface 13 on the second enveloping structure element 3 when the enveloping structure is assembled. The support surfaces 12, 13, like the extension 8 and the receptacle 9, function as guides and produce a partial positive fit when the enveloping structure is assembled, which defines the position of the enveloping structure elements 2, 3 before establishing a form-fitting or material-fitting relationship in the insertion direction.

A filling opening 14 is provided in the inner wall 7 of the second enveloping structure element 3 . The filling opening 14 is used to introduce filling material into the receptacle 9 in order to create a form fit with the first enveloping structure element 2 via the form-fitting means 10 on the extension 8 . The filling material can be supplied under pressure through the opening 14 in order to ensure that the receptacle 9 is completely filled and, in the hardened state of the filling material, that there is a complete form fit with the form-fitting means 10 . The filling material is preferably designed to be cold curable or hardenable at low temperatures in order to avoid additional thermal stress on the second enveloping structure element 3 .

2 shows a section of an assembled enveloping structure, the enveloping structure elements 2, 3 of which are connected to one another in a form-fitting and material-locking manner according to the invention in order to form an enveloping structure 1. The form fit between the first structural envelope element 2 and the second structural envelope element 3 is achieved via the extension 8 with the form-fit means 10 and the filling material 24 accommodated in the receptacle 9 . For this purpose, the filling material 24 can be conveyed into the receptacle 9 via the filling opening 14 . Because the filling material 24 is fed in under pressure, it is ensured that the form-fitting means 10 is ultimately completely surrounded by the filling material 24 .

The filling material 24 can in particular penetrate into the indentation 15 of the form-fitting means 10 . If the filling material 24 then hardens, it is connected in a form-fitting manner to the form-fitting means 10 . At the same time, the filling material 24 in the hardened state is positively connected to the second enveloping structure element 3 via the receptacle 9 .

The receptacle 9 tapers upwards, ie counter to the direction of insertion E. Hardened filling material 24 located in the receptacle consequently also forms a form fit with the receptacle 9 and cannot be displaced counter to the direction of insertion. Furthermore, part of the filling material 24 can remain in the filling opening after the filling process. Above the filling material 24 in the filling opening 14 creates a further form fit when the filling material 24 hardens.

The interlocking between the first structural envelope element 2 and the filling material 24 and the second structural envelope element 3 and the filling material 24 thus form a positive connection 25 between the first structural envelope element 2 and the second structural envelope element 3. In addition, the filling material 24 can have an adhesive effect and the first structural envelope element 2 via the extension 8 adhesively connect to the second shell structure element 3 .

The two outer walls 4, 6 of the shell structure elements 2, 3 are connected to one another by a weld seam 11. The weld seam 11 forms a material connection that acts parallel to the form-fitting connection 25 described above. The weld seam 11 and the form-fitting connection 25 together form a sufficiently rigid connection that enables an envelope structure 1 to be constructed with high rigidity.

The specific embodiments described and illustrated are not binding for the practice of the invention, but may be suitably modified within the scope of the claims without departing from the scope of the present invention.

Reference List

E

insertion direction

Q

transverse direction

B

width (pick-up opening)

b

width (extension)

1

shell structure

2

First shell structure element

3

Second shell structure element

4

Outer wall (first shell structure element)

5

Inner wall (first shell structure element)

6

Outer wall (second shell structure element)

7

inner wall (second shell structure element)

8th

extension

9

recording

10

form-fitting means

11

Weld

12

support surface (first shell structure element)

13

support surface (second shell structure element)

14

filling hole

15

indentation

16

intake opening

17

bearing surface (first shell structure element)

18

bearing surface (second shell structure element)

19

Welding surface (first shell structure element)

20

Welding surface (first shell structure element)

21

weld pool backup

22

strut

23

strut

24

filling material

25

Positive-locking connection

Claims (15)

1. An envelope structure (1) for a car body for a vehicle, comprising a first envelope structure element (2) and a second envelope structure element (3), wherein

   - the first envelope structure element (2) and the second envelope structure element (3) each comprise an outer wall (4, 6) and an inner wall (5, 7),

   - the first envelope structure element (2) is provided with an extension (8) extending between the outer wall (4) and the inner wall (5) in an insertion direction (E),

   - the second envelope structure element (3) is provided with a receptacle (9) opening between the outer wall (6) and the inner wall (7) in a direction opposite to the insertion direction (E) for inserting the extension (8),

   - the extension (8) comprises a positive locking means (10),

   - the receptacle (9) is filled with a filling material (24),

   - a positive locking is established by the extension (8) accommodated in the receptacle (9) and the filling material (24) surrounding the positive locking means (10) at least in sections,

   - the first envelope structure element (2) and the second envelope structure element (3) are connected to each other by a weld seam (11).
2. The envelope structure (1) according to claim 1, wherein the weld seam (11) is arranged at opposite surfaces of the inner wall (5, 7) or the outer wall (4, 6) of the first envelope structure element (2) and the second envelope structure element (3).
3. The envelope structure (1) according to any of the above claims, wherein the weld seam (11) is applied to the envelope structure (1) from the outside.
4. The envelope structure (1) according to any of the above claims, wherein the first or the second envelope structure element (2, 3) comprises an extension engaging behind the weld seam (11) from the inside, which extension is suitable for forming a weld pool backing.
5. The envelope structure (1) according to any of the above claims, wherein the first and/or second envelope structure elements (2, 3) are formed by extruded profiles.
6. The envelope structure (1) according to any of the above claims, wherein the first envelope structure element (2) including the extension (8) and/or the second envelope structure element (3) including the receptacle are formed by an extruded profile.
7. The envelope structure (1) according to any of the above claims, wherein the receptacle (9) tapers in a direction opposite to the insertion direction (E).
8. The envelope structure (1) according to any of the above claims, wherein at least one inner wall (5) of the receptacle is at a distance from the positive locking means (10).
9. The envelope structure (1) according to any of the above claims, wherein the second envelope structure element (3) is provided with a filling opening (14) penetrating the outer wall (6) or inner wall (7) of the second envelope structure element (3) and leading into the receptacle (9).
10. The envelope structure (1) according to any of the above claims, wherein the insertion direction (E) is substantially parallel to the outer wall (4) and/or the inner wall (5) of the first envelope structure element (2).
11. The envelope structure (1) according to any of the above claims, wherein the extension (8) is received in the receptacle (9) while the outer walls (4, 6) and/or inner walls (5, 7) of the envelope structure elements (2, 3) are aligned with each other.
12. The envelope structure (1) according to any of the above claims, wherein the extension (8) comprises an indentation (15) extending substantially perpendicular to the insertion direction (E).
13. The envelope structure (1) according to any of the above claims, wherein the filling material (24) comprises a thermoset.
14. The envelope structure (1) according to claim 13, wherein a positive locking between the first envelope structure element (2) and the second envelope structure element (3) is established via the filling material (24) in a cured state.
15. A method of manufacturing an envelope structure (1) according to any of the above claims, comprising the steps of:

    a) Providing a first and a second envelope structure element (2, 3);

    b) Subsequently, inserting the extension (8) of the first envelope structure element (2) into the receptacle (9) of the second envelope structure element (3);

    c) Subsequently, filling the receptacle of the second envelope structure element (3) with a filling material (24), in particular a cold-curing filling material;

    d) Subsequently, curing the filling material (24);

    e) One-sided welding of the first envelope structure element (2) to the second envelope structure element (3).

Images