EP2401189A1

EP2401189A1 - Support frame structure of a vehicle and method for producing the same

Info

Publication number: EP2401189A1
Application number: EP10701806A
Authority: EP
Inventors: Matthias Stangl; Ralph Eppelein
Original assignee: Bayerische Motoren Werke AG
Current assignee: Bayerische Motoren Werke AG
Priority date: 2009-02-27
Filing date: 2010-01-09
Publication date: 2012-01-04
Also published as: CN102245461A; CN102245461B; WO2010097141A1; DE102009010974A1

Abstract

The invention relates to a support frame structure of a vehicle, in particular an axle support, substantially made of two longitudinal beams and two transverse beams supporting the same against each other, each designed as hollow profiles made of at least two formed parts joined at joint areas extending substantially in the longitudinal axis of each hollow profile, wherein a first formed part of each beam is integrally connected to the first formed part of the other beam, in that an upper shell of the support frame structure having still open longitudinal and transverse beams is formed by bending from an initially flat and suitably cut sheet metal structure, said beams each then being completed as a hollow profile by welded cover sheets as second or further formed parts. An upper shell thereby forms an external structure made of a flat cover structure and an edge structure protruding therefrom at an angle, and made of at least two arm structures, each extending outward from a corner area forming a node point, in which a longitudinal beam abuts a transverse beam, approaching a direction of an angle bisector in the top view. Each arm structure is complemented by a welded closure sheet metal, forming a hollow body that is a support arm of the support structure.

Description

Support frame structure of a vehicle and manufacturing method thereof

The invention relates to a support frame structure of a vehicle, in particular an axle, consisting essentially of two so-called. Longitudinal supports and two of these mutually supporting so-called. Cross-straps, which are each designed as hollow profiles. Furthermore, the invention relates to a method for producing such a support frame structure. For technical reasons, reference is made to DE 102 60 529 A1, for example, in addition to EP 760 327 B1.

Vehicle support frame or axle according to the preamble of claim 1 must meet a variety of requirements. In addition to the space constraints, of course, strength requirements are to be considered and, moreover, these support frames should be simple and economical, ie inexpensive to produce. For axle carriers of eg. Passenger cars, the type shown in the second-mentioned font is currently widely used. In this case, a substantially rectangular frame is assembled from hollow sections, in particular from tubes, in particular welded, are provided in the quasi-elongated corner bearing points for supporting the axle beam on the vehicle underbody or on the two vehicle side rails. On the axle, several articulation points are, for example. In the form of tabs or the like. Provided for wheel-guiding arm and possibly for a final drive. Between the individual articulation points and between the articulation points and the bearing points of the axle beam while a favorable flow of force flow should be possible. In the present case, it has now been recognized that improvements are possible both with regard to the latter criterion, namely a "power flow-optimized" design, and with regard to the criterion of economical manufacturability, which are to be shown herewith (= object of the present invention).

For a support frame structure according to the preamble of claim 1, the solution of this problem is characterized in that each hollow profile consists of at least two in substantially longitudinal direction of the respective hollow profile joining portions assembled moldings, and that of each carrier a first mold part with the first moldings of Another carrier is integrally connected by a so-called. Upper shell of the support frame structure is then formed with an open longitudinal beams and cross beams from a first level and suitably trimmed sheet metal structure, which are each completed by so-called. Strike plates as second or further moldings to form a hollow profile. A corresponding method claim is directed to the production of such a support frame structure and advantageous embodiments and further developments are content of the respective subclaims.

A supporting structure according to the invention can be produced much simpler than the known supporting structures assembled from prefabricated hollow profiles, since in addition to the production of joining compounds in a final processing step of the production process analogously to the prior art, preferably only two extremely simple and easily controllable forming processes are carried out in the form of welded joints Need to become. Accordingly, a flat sheet is first appropriately trimmed, which is preferably done by punching (shearing), and then individual sections of this sheet are bent. Simplified, one could compare the first two steps of the manufacturing process of a support frame structure according to the invention with the production of a rectangular lid of a cardboard box, after which a flat sheet of cardboard is first suitably trimmed and then the edges of the lid are formed by bending. The edges of the cardboard box cover thereby form the so-called first molded parts of the hollow profiles of a support structure according to the invention, which are assembled into a frame first molded parts after these two processing steps on the lying between the edges flat area (the lid or the upper shell) are related.

The subsequent third manufacturing process step is not provided in the production of a cardboard box lid, in the present case, but in the production of a support frame structure according to the invention, however, required for the formation of hollow profiles. Here, the (in the case of a simple rectangle four) transformed "edges", which in turn may each contain a substantially longitudinally extending bending edge and thus need not be flat, by attaching suitably shaped so-called. Strike plates in so-called. Joining areas (four These joining regions between the bent "edges" or first molded parts of the hollow profiles and the so-called striking plates (as second or further molded parts of a hollow profile) run essentially in the longitudinal direction of the respective hollow profile. Preferably, these striking plates are not even, but have a substantially extending in the longitudinal direction of the respective hollow profile bending edge, wherein also preferably also the so-called. Strike plates or the second and further moldings of ultimately a longitudinal support or a transverse support of the support frame structure forming hollow profiles considered in itself are or will be prepared in the manner described, namely by bending an initially flat and suitably trimmed sheet metal structure. What finally the nature of Affected connection between the moldings, it may be cohesively or positively; Preferably, this is a welded joint, alternatively, a crimp connection selected.

Due to the virtually exclusive use of Biegeumformteilen is the one-time effort that must be operated for mass production of a support frame structure according to the invention, extremely low. There is little investment required in terms of machinery and advantageously, such a support frame structure can be made quickly and inexpensively in prototype construction with a conventional Spengler equipment. In the mass production process, in turn, a high degree of repeatability is obtained and any necessary changes can easily be incorporated, for example by a slight change in the sheet thickness used. The respective bending angle, which include bent portions of the originally flat sheet metal structure with the original plane thereof is advantageously in the range between 10 ° and 90 °.

Of course, a support frame structure produced in this way, for example in the form of an axle carrier, must also meet the functional requirements and the strength requirements. A sheet metal part such as a support structure according to the invention can then cope with these requirements when the main supporting elements of the sheet metal structure are formed by their bending edges or the environment of the bending edges, while recorded by the sheet metal part thrust loads of so-called. Sheet metal fields are taken, which amplified by strike plates could be. Torsion loads on the sheet metal part are best absorbed by closed hollow sections, while open structures can be used in areas of major bending load. A support frame structure produced according to the invention contains these components, namely hollow sections, sheet metal fields as so-called push fields and bending edges, which can then be respectively arranged and designed according to the loads occurring. Preferably, in this sense, the each substantially essentially a force flux line descriptive bending edges in a straight line and preferably in the direction of the vehicle longitudinal axis or perpendicular to this.

In reworking the known in their basically proven structure Achsträger can on a support frame structure according to the invention said upper shell form an outer structure consisting essentially of a flat so-called lid structure - acting as a "shear field" - and from an angularly projecting so-called. forming said supports - and consist of at least two so-called. Arm structures, each of a so-called. Node forming corner region, in which metaphorally a longitudinal beam collides with a cross member protrude in plan view approximately in the direction of an angle bisector to the outside The free ends of these arm structures can then be provided receptacles for bearing bushes, via which the axle carrier (or the like.) Is mounted on the vehicle or on supports of the vehicle body.

Also to a closed hollow profile, more precisely to a hollow body, which is characterized by high strength and low weight, can be completed an arm structure by a substantially pyramid-shaped strike plate, which is preferably also formed by bending an initially flat and suitably trimmed sheet metal structure. This hollow body then forms a support arm of the support structure and is provided for this purpose at its free end with an already mentioned receptacle for a bearing bush, which in turn is advantageously in turn formed by chipless forming an initially flat and suitably trimmed sheet metal structure, which is then welded to a support arm becomes. If the striker plate of a support arm protruding from a named junction (= corner region of the support frame structure) is supported not only at the mentioned arm structure, but also at the ends (longitudinal support and / or transverse support) terminating in this junction away from the ends thereof, so that in this node a hollow body Structure is formed with more chambers therein, so hereby particularly high stiffness requirements with respect to bending and torsion can be met. In the same sense, an edge region of the or an arm structure with an edge region of the adjacent edge structure mentioned (this is formed by said first mold parts) connected in a force-transmitting manner, in particular welded.

In their entirety, the strength or rigidity of a support frame structure according to the invention can be further increased if, in addition to the already existing (and already mentioned) cover structure, a further so-called push field supported on all supports is provided. This can then form an interplay with the cover structure quasi a floor structure of the support frame structure. In order to optimize the weight of a support frame structure according to the invention, perforations may be provided in planar sections of the support frame structure, which apertures are designed in particular with regard to the loads to be absorbed by these two-dimensional sections and serve to reduce the weight. Furthermore, already above recordings for example. Handlebars or the like. Called, which may be provided on an axle or generally on a support frame structure. Also, such recordings can, if they are special moldings, advantageously be formed by bending an initially flat sheet metal structure formed tabs and preferably mounted near a bending edge on a support frame structure according to the invention.

In the following, an embodiment of the present invention will be described with reference to the accompanying figures 1-5. Shown is an inventive rear axle of a passenger car in Figures 1, 2 in a view from above (obliquely spatial or vertical), and in Figures 3, 4 in a view from below (obliquely spatial or vertical), while in the figure sequence 5a, 5b, 5c quasi the "settlement" of this axle carrier is shown, that is, with the exception of some missing parts show Figures 5a, 5b, 5c, the still flat sheet metal structures before their bending deformation, from which after appropriate bending deformation of the axle according to the figures 1 - 4 is assembled or is. Of course, the same components in all figures are identified by the same reference numerals, however, in the case of the initially flat and suitably trimmed sheet metal structures in Figures 5a, 5b, 5c, in each case a "*" is appended to the reference number of the respective component Achsträger with respect to the longitudinal center axis L of the vehicle, which is equal to the longitudinal center axis of the axle carrier, reference numerals for symmetrically existing components or components entered only in one of the two symmetry halves.

The reference numeral 1 denotes the so-called upper shell of the axle beam according to the terminology used hitherto, which is or is formed from a first flat top sheet metal structure 1 ^*, suitably cut by punching, by bend forming along different respective rectilinear bending edges a-e, cf. , this first Figure 5a.

By individually bending over with respect to the bending edges a, c and e outer portions 11 a *, 11c * and 11e * of the initially flat upper shell sheet metal structure 1 ^* are essentially the so-called. First molded parts 11a, 11c and 11e according to the terminology used above It is expressly pointed out that the first molded parts 11 a (or 11 a *) and 11 c (or 11 c *) extend over the longitudinal center axis L (of the axle carrier or of the vehicle). The sections 11a ^* and 11e ^* are respectively bent over a further bending edge f or g running parallel to the bending edge a or e within the respective section, so that the resulting molded parts 11a and 11e are not plane. The abovementioned bending edges a, c, ef, g run in the longitudinal direction of the respective molded part, which, as explained below, forms part of a hollow body or of a support with a longitudinal section extending in this longitudinal direction. the longitudinal axis becomes. This essentially forms the so-called edge structure R according to the terminology used above. In addition, in the section marked 111e ^* and in the lowermost portion in FIG. 5a (uppermost section in the mirror symmetry to the longitudinal center axis L) of the molded sheet metal structure 11e ^* further subregions of this section 111e ^* for clarity are not further delineated with further separate reference numerals rectilinear bending edges h, i, k bent, which will be discussed again in the following paragraph.

By individually bending relative to the lying in the four corners E of the upper shell sheet metal structure 1 ^* bending edges b and d outer portions 12b * and 12d ^{* of} the initially flat upper shell sheet metal structure 1 ^* (see Fig. 5a further) are substantially the so-called arm structures 12b and 12d formed terminology used above, but said in the previous paragraph said section 111e ^* of the arm structure 12d ^* adjacent molding 11e ^* after appropriate bending and joining via a welded joint S is a part of the arm structure 12d, in particular the Figures 1, 2 can be removed. In this respect, an edge region of the arm structure 12d is connected, in particular welded, to an edge region of the adjacent edge structure R, namely with its section 111e, in a force-transmitting manner. Incidentally, the sections 12b ^* and 12d ^{* also have} further (rectilinear) bending edges I, m, no, p (see FIG. 5a), around which individual sections of these sections are bent again, in order ultimately to form the (two) arm structures 12b and to form the (two) arm structures 12d, which protrude outwardly from each corner region E approximately in the direction of an angle bisector and are each part of the support arms (according to the terminology above).

After the bending of the portions of the initially flat upper sheet metal sheet structure 1 ^* lying outside of the bending edges a-e has taken place, the one inside thereof forms a substantially closed ring

ANS Bending edges a - e lying area of the upper shell sheet metal structure 1 * the so-called lid structure D terminology used above. In this essentially rectangular cover structure D, from whose corner regions E the arm structures 12b and 12d protrude approximately in the direction of an angle bisector of the respective corner angle, a central opening 14 is provided for weight reduction taking into account the rigidity requirements of the axle beam.

The first molded part 11a as well as the section of the cover structure D connected thereto via the bending edge a and extending to the central opening 14 is provided with two strike plate sheet metal structures 2 * (see FIG Bending around bending edges r, s, t are formed into suitably shaped striking plates 2, joined together by welding in so-called joint areas suitably. As a result, inter alia, the front cross member Qv of the axle beam (as a hollow profile) is formed (see, for example, Fig.2).

The first molded part 11 e and the section of the lid structure D connected thereto via the bending edge e and extending as far as the central opening 14 is provided with a strike plate sheet metal structure 3 ^* which is likewise flat and suitably trimmed, bent over by bending edges u, v is formed into a suitably shaped striking plate 3 (cf., Fig. 5b), suitably joined together by welding in so-called joining regions. As a result, the rear cross member Qh of the axle beam (as a hollow profile) is formed (see Fig.3, 4).

The first molded part 11c as well as the section of the lid structure D connected thereto via the bending edge c and extending to the central opening 14 is closed by two strike plate sheet metal structures 4 *, also flat and suitably trimmed, which are bent over by bending edges w, x a suitably shaped strike plate 4 are formed (see Fig.5b), by welding in so-called together. As a result, in particular, a longitudinal member LT of the axle beam (as a hollow profile) is formed (see Fig. 3, 4).

The above-mentioned rear arm structures 12d form after joining (welding in so-called joining regions) with the already mentioned section 111e of the molded part 11e and with two also initially flat and suitably cut strike plate metal structures 5 ^* , which in turn are bent over bending edges y several times, z are formed to suitably here each in the form of a pyramid shaped striking plates 5 (see Fig. 5b), the rear support arms 15 of the axle carrier (as a hollow body), see. 3, 4. The already mentioned front arm structures 12b form after the already briefly mentioned bending around the bending edges π, o, p running inside thereof and, after suitable joining, with strike plates also provided for this purpose which, for the sake of simplicity, are shown in the figures. Sequence 5 (ac) are not shown but analogous to the explained (and shown) striking plates are formed by bending from an initially flat sheet metal structure, the front support arms 16 of the axle carrier in the form of hollow bodies.

In FIG. 5c, the reference numerals 6 * and 8 ^{* designate} so-called first flat and suitably trimmed plate-shaped sheet metal structures, from which bending edges (not shown) are formed by bending over tabs 6, 8, which are subsequently marked with the axle carrier on the welded to desired locations. At these tabs 6, 8 can be supported in the functional use of this axle carrier wheel-guiding arm or be. Finally, the reference numeral 7 ^* denotes a so-called initially flat and suitably trimmed receiving sheet metal structure, from which a receptacle 7 for a bearing bush is formed by bending over suitable bending edges, which is then welded to the free end of each support arm 16. Also for the free end of the two rear support arms 15 similar bearing bush receptacle are provided, however, the first planar sheet metal structure is not shown figuratively. Finally, it should be expressly pointed out that the detailed design of the axle beam presented here or of the support frame structure presented here can deviate from the above explanation as well as the attached figures in a large number of details. Much more important is the basic manufacturing process, according to which first flat and suitably trimmed sheet metal structures by possibly multiple bending of individual sections, this multiple bending can be carried out step by step in succession, so to speak "origami technique" spatial components are formed, which after suitable joining at least in sections In the present case, the upper shell 1 formed by bending over an initially flat and suitably trimmed sheet metal structure forms a central spatial component to which the further substantially similarly shaped components are added, wherein Deviating from the exemplary embodiment explained, this joining can also take place in a form-fitting manner along suitably extending joint regions With the exception of the opening 14 in the cover structure D, I have mentioned further openings provided in other flat sections of components of the support frame structure, which are each provided taking into account the loads to be absorbed in order to minimize the weight of a support structure according to the invention.

Claims

claims

1. supporting frame structure of a vehicle, in particular axle, consisting essentially of two so-called. Longitudinal supports (LT) and two mutually supporting so-called. Transverse supports (Qv, Qh), which are each designed as hollow profiles, characterized in that each Hollow profile of at least two in substantially longitudinal direction of the respective hollow profile joining portions assembled molded parts (11a, 11c, 11e, 2, 3, 4), and that of each carrier (Qv, Qh, LT), a first molded part (11a, 11c , 11e) is integrally connected to the first molded parts (11a, 11c, 11e) of the other supports (Qv, Qh, LT) by bending from an initially flat and suitably trimmed sheet metal structure (1 ^* ) by a so - called upper shell (1) Support frame structure with then still open side rails (LT) and cross members (Qv, Qh) is formed, each of which is completed by so-called. Strike plates (2, 3, 4) as second or further moldings (2, 3, 4) to form a hollow profile are handed down.

2. supporting frame structure according to claim 1, characterized in that the strike plates (2, 3, 4) by bending forming an initially flat and suitably trimmed sheet metal structure (2 *, 3 *, 4 *) are formed.

3. supporting frame structure according to claim 1 or 2, characterized in that the closing plates (2, 3, 4) are connected to the first mold parts along the joining regions cohesively or positively.

4. Support frame structure according to one of the preceding claims, characterized in that the so-called. Upper shell (1) forms an outer structure consisting essentially of a flat so-called. Cover structure (D) and an angularly projecting from this so-called edge structure (R) and consists of at least two so-called. Arm structures (12b, 12d), each of a so-called. Node forming corner region (E), in which the end of a side rail (LT) the end of a cross member (Qv, Qh) is adjacent, in plan view protrude approximately in the direction of an angle bisector to the outside.

5. supporting structure according to claim 4, characterized in that an edge region of an arm structure (12d) connected to an edge region of the adjacent edge structure (R) in a force-transmitting manner, in particular welded (S).

6. Support structure according to claim 4 or 5, characterized in that an arm structure (12b) by a substantially pyramidal striking plate (5), which is preferably also formed by bending an initially flat and suitably truncated sheet metal structure (5 ^* ), to form a hollow body is supplemented, which forms a support arm (15) of the support structure.

7. Support structure according to claim 6, characterized in that the striking plate (5) of a of a node or corner region (E) projecting support arm (15, 16) not only on the arm structure (12b), but also on the in this corner region (E) ending supports (cross member Qv, side member LT) is supported off the ends thereof, whereby in this corner region a hollow body structure is formed with several chambers therein.

8. supporting frame structure according to one of the preceding claims, characterized in that each bending edge (a - z) is rectilinear and essentially describes a force flux line.

9. supporting frame structure according to one of the preceding claims, characterized in that in addition to the cover structure (D) another on all carriers supported so-called. Schubfeld is provided.

10. Support frame structure according to one of the preceding claims, characterized in that by bending an initially planar sheet metal structure (6 *, 8 ^* ) shaped tabs (6, 8) for receiving attachments, in particular links, are mounted near a bending edge.

11. Support frame structure according to one of the preceding claims, characterized in that openings (14 and more) are provided in planar sections of the support frame structure.

12. A method for producing a supporting frame structure of a vehicle, in particular an axle beam, the / essentially of two so-called. Longitudinal beams (LT) and two of these mutually supporting so-called. Cross members (Qv, Qh), which are each formed as hollow profiles, characterized in that each hollow profile consists of at least two molded parts (11a, 11c, 11e, 2, 3, 4) in a substantially longitudinal direction A so-called upper shell (1) of the supporting frame structure with then still open longitudinal members (LT) and cross members (Qv, Qh) is formed from an initially flat and suitably trimmed sheet metal structure (1 ^* ) by bending such that from each support (LT, Qv, Qh) a first mold part (11a, 1c, 11e) is integrally connected to the first mold parts (11a, 1c, 11e) of the other supports (LT, Qv, Qh), and in that each carrier (LT, Qv, Qh) is completed by so-called strike plates (2, 3, 4) as second or further molded parts (2, 3, 4) to form a hollow profile.

13. A method for producing a support frame structure according to claim 12, characterized in that the strike plates (2, 3, 4) from an initially flat and suitably trimmed sheet metal structure (2 ^* , 3 ^* , 4 *) are formed by bending.

14. A method for producing a support frame structure according to claim 12 or 13, characterized in that the striker plates (2, 3, 4) with the first mold parts (11 a, 11 c, 11 e) are joined material-locking or form-fitting along joining regions.