The invention relates to a rigid motor vehicle axle comprising an axle body which is hollow at least in some regions and has two adapter pipe sections joined together from half shells along a longitudinal assembly joint by welding, with axle-supporting and axle-guiding components being fastened or coupled in the region of the adapter pipe sections.
German Patent No. DE 103 37 193 A1 discloses a rigid vehicle axle of this type. In each of the outer regions, the axle body of the rigid axle has an axle pipe section which is comparable to the adapter pipe section previously mentioned. Each axle pipe section is formed from two half shells, with them being welded to each other along their longitudinal assembly joint. For the fastening of axle-supporting and/or axle-guiding components, a plurality of fastening sleeves are welded laterally to the axle pipe sections. As an alternative to this, in another variant embodiment, special saddle-shaped adapter elements are fastened to the upper and lower sides by welding. The fastening of these connecting elements by welding has the disadvantage that, if a weld fractures, the rigid axle can become detached from the vehicle body in an uncontrolled manner.
It is an object of the present invention to overcome the prior art problem by developing a rigid vehicle axle, the connecting elements of which—despite being welded to the axle body—follow the design principle of “limited failure”. The construction space required by the axle is not to be enlarged.
In a rigid motor vehicle axle comprising an axle body which is hollow in at least some regions and which has two adapter pipe sections joined together from half shells along a longitudinal assembly joint by welding, with axle-supporting and axle-guiding components begin fastened or coupled in the region of the adapter pipe sections. For this purpose, the respective adapter pipe section has at least two recesses. At least one connecting element is partially housed within the hollow regions of the axle and extends outwardly through the recesses with a form fit. The adapter pipe section and the connecting element are connected to each other along an insertion joint with a cohesive material joint proximate the adapter pipe section recesses.
The present invention develops a rigid vehicle axle, the connecting elements of which provide limited failure despite being connected to the axle body with a cohesive material joint.
For this purpose, the respective adapter pipe section has at least two recesses per wheel side of the axle body. At least one connecting element is inserted into the recesses per wheel side of the axle body—with a form fit and, if appropriate, with a relatively large amount of play—with an assembly joint being produced between the connecting element and the respective adapter pipe section. The adapter pipe section and the connecting element are connected to each other along the assembly joint with a cohesive material joint. In the event of a relatively large amount of play between the connecting element and the respective adapter pipe section, the connection, which is designed, for example as a weld, is to be provided in a centering device. Alternatively, the components to be joined can be machined in such a precise manner that the components can be joined together with a form fit in a manner largely free from play and a connection in a centering device can be dispensed with.
Accordingly, there is at least one connecting element in the form of an insert in each wheel-side axle body half. The connecting element, which is inserted into corresponding recesses of the half shells with a form fit and protrudes, for example, to the front and rear, is integrated nondetachably in the axle body during the production of the welds connecting the half shells with a cohesive material joint. The form fit already prevents separation of the components. In addition, the connecting element is connected all around along the edges of the recesses to the axle body with a cohesive material joint, for example, by means of a welding process.
The construction principle of limited failure is thereby realized for the connection of the axle-guiding and axle-supporting components. Should, in the event of an overloaded rigid axle, a connection, such as, for example, a weld, tears in the connecting element region of the adapter pipe section which, among other things, is loaded to the maximum by bending, although the axle-guiding and axle-supporting components may become loose, this does not lead to loss of the axle because of the form fit. According to the principle of limited failure, an extremely hazardous failure of the connection, such as, for example, of a weld, is therefore permitted during the vehicle use time without severe consequences being able to occur as a result. The vehicle driver becomes aware of a defective weld at the latest during the daily routine check due to a loss of oil from the axle. In the case of nondriven axles, the axle bodies of which as a rule do not receive any lubricating oil, unmissable rattling noises arise in the damaged axle body region at the latest when the vehicle is next idling.
Further details of the invention will become more readily apparent from the following description of the expedient embodiments thereof on the basis of the accompanying drawings.
According to
The cylindrical casing (12), for example manufactured as a sheet-metal part, sits, if appropriate, centrally, in the geometrical center of the axle body (10). A bearing bracket (13), for example, is arranged on the cylindrical casing (12). This bearing bracket (13) is used to support the axle body (10) on the vehicle frame via a wishbone (not illustrated). At the sides, the cylindrical casing (12) has a respective large opening with, for example, an oval cross section. A funnel-like intermediate piece (14), for example, is welded on at this location. It ends in a flat end-face joining contour (15) in the shape of a circular ring.
The adapter pipe sections (20) adjoin the intermediate pieces (14) on both sides at the respective joining contour (15). Each adapter pipe section (20) here comprises, for example, a lower and an upper half shell (21, 22), manufactured, for example, from steel sheet, see
Towards the axle end piece (17), the adapter pipe section (20) ends in a cross section likewise, for example, in the shape of a circular ring. The axle end piece (17) is fastened there, for example, by friction welding. The joining contour (15) in the shape of a circular ring lies with its geometrical center on the axle body axis (5). In addition, it is oriented normally to the axle center line (5). In this exemplary embodiment, the same also applies to the joining contour (16).
In
A brake anchor plate flange (19) is fastened on each adapter pipe section (20), for example by welding. The individual brake anchor plate flange (19) is oriented normally to the axle center line (5). The brake lining support and brake caliper (not illustrated) are fastened to the individual brake anchor plate flange (19).
All of the axle body parts, including the axle stub (18), form a common cavity, which, if appropriate partially separated—below the drive half-shafts—by splash walls, constitutes a storage space for lubricant.
In the case of asymmetrical axle bodies, adapter pipe sections (20) of different length are arranged between the intermediate piece (14) and the axle stubs (18).
Pursuant to the present invention, in the adapter pipe section (20), as shown in
According to
During the production process of the axle body (10), the individual connecting element (41) is placed between the half shells (21, 22) in order subsequently to be fixed in the recesses (23, 24) during welding of the two longitudinal assembly joints (31, 32). In the region of the respective connecting element (41), the individual longitudinal assembly joint (31, 32) is divided into the assembly joint (33, 34) which is guided around the connecting element (41). The connecting element (41) is welded to the adapter pipe section (20) along the assembly joint (33, 34). All of the welds (71, 72) of this region are at least oil tight.
Regardless thereof, the longitudinal assembly joints (31, 32) and the assembly joints (33, 34) may also be three-dimensionally curved surfaces, so that the corresponding welds (71, 72) follow curves curved three-dimensionally.
In order to join together the individual pre-manufactured, if appropriate finished axle body parts, with as little distortion as possible, use is made, for example, of welding processes, such as laser or plasma welding. The welds (71, 72) tightly sealing the respective connecting element (41-45) to the half shells (21, 22) of the adapter pipe sections (20, 120) may be, inter alia, flat, curved or hollow welds. DHY welds are also conceivable.
According to
The connecting element (42) which is arranged centrally between the half shells (21, 22) in the vertical direction has, in the region in which it penetrates the adapter pipe section (120), an at least approximately rhomboidal cross section with rounded corners, with the result that the component wall thickness between the fastening bores (61), see also
According to
According to
The intermediate spaces (37, 38) are partially filled, for example, with an “APM aluminium foam”. The APM foam is a bonded mixture of premanufactured, small-volume metal foam elements (58). The metal foam elements (58) are, for example, in each case balls of identical size. The smallest diameter of the metal foam elements is smaller in this case than the gap (56). The metal foam elements (58) are encased with adhesive or are introduced together with adhesive as a compact into the intermediate spaces (37, 38) to be filled with foam. The mixture is heated in the adapter pipe section (120) to approx. 180° C. In the process, the adhesive is activated. It connects the metal foam elements firstly to one another and secondly to the connecting element (42) and the adapter pipe section (120).
The bonded metal foam elements (58) therefore have a stiffening and noise-damping effect. As an alternative to this, a metal foam or another curing adhesive compound can be sprayed into the intermediate spaces (37, 38) via certain bores. In
The spring console (81), as shown in
As a further variation, the clamp web (67) can be omitted, and so, for example, two separate transverse clamps (65, 66) situated next to each other are used.
The adapter pipe section (120) bears with its lower stop surfaces (51, 52) of the connecting element (45) against the spring console (81). According to
In the case of the variant according to
By contrast, the adapter pipe section (120), of
As a further characteristic, the connecting element (43) has a joint eye (57), for example for the coupling of a link or a connecting rod of a U-stabilizer. The joint eye (57) is integrally formed here on the front fastening tab (48). If appropriate, the connecting element (43) can also be used only as a support of the joint eye (57) or of a comparable functional part. Accordingly, the fastening tab (49) lying opposite the joint eye (57) does not have to protrude over the outer wall (39) of the adapter pipe section (120).
The connecting elements (41-45) can be used in the axle bodies of all types of rigid axles, such as, for example, of steered and unsteered, of driven and undriven axles or else of lift axles.
It is also conceivable not to weld but rather to adhesively bond the half shells (21, 22) along the longitudinal assembly joints (31, 32) and the assembly joints (33, 34). The same applies in particular if the corresponding axle body parts are to be manufactured from fiber-reinforced plastics or comparable composite materials.
Number | Date | Country | Kind |
---|---|---|---|
10 2006 005 773.2 | Feb 2006 | DE | national |
10 2006 017 421.6 | Apr 2006 | DE | national |