Axle carrier for a multi-track vehicle

Abstract

Axle support (2) for a multi-track motor vehicle (1), comprising a first longitudinal member (4), a second longitudinal member (5) and at least one cross member (6, 22) connecting the first longitudinal member (4) and the second longitudinal member (5), wherein at least one link (8) for connecting a wheel carrier for a wheel (3) of the motor vehicle (1) is articulated at bearing points (7) of the first longitudinal member (4) and the second longitudinal member (5), wherein the bearing points (7) are each arranged in a bearing connection region (11) of the corresponding longitudinal member (4, 5), in which the longitudinal member (4, 5) has a lower rigidity perpendicular to its longitudinal extent than away from the bearing connection region (11), wherein at least one of the bearing connection regions (11) is present as an outwardly deflected offset region of the respective longitudinal member (4, 5), and wherein the offset region is provided at two spaced-apart connection points (18, 19) in Supporting areas (16,17) of the longitudinal member (4,5), characterized in that the offset region merges into one of the support regions (16, 17) via at least one bend (26, 27), wherein in the bend (26, 27) at least one stiffness-reducing wall opening (28) is formed in the wall of a support profile of the respective longitudinal member (4, 5).

Description

[0001] The invention relates to an axle carrier for a multi-track motor vehicle, having a first longitudinal member, a second longitudinal member and at least one cross member connecting the first longitudinal member and the second longitudinal member to one another, wherein at least one link for connecting a wheel carrier for a wheel of the motor vehicle is articulated at bearing points of the first longitudinal member and the second longitudinal member, wherein the bearing points are each arranged in a bearing connection region of the corresponding longitudinal member, in which the longitudinal member has a lower rigidity perpendicular to its longitudinal extent than away from the bearing connection region, wherein at least one of the bearing connection regions is present as an outwardly deflected offset region of the respective longitudinal member.

[0002] The axle carrier connects the wheel carrier to the motor vehicle, in particular to the vehicle body. The body is preferably designed as a self-supporting body. The axle carrier can also be referred to as a subframe or subframe. It is rigidly connected to the body, for example, by bolts. In this case, it is referred to as an integral carrier. Alternatively, it can be connected to the body via dampers, for example, via vibration-damping connecting elements.

[0003] The axle carrier is designed for multi-track motor vehicles. Accordingly, it offers the possibility of connecting multiple wheel carriers, with at least two of the wheel carriers being assigned to the same wheel axle of the motor vehicle, for example, a front axle or a rear axle. This description always refers to only one of the wheel carriers. However, it is self-evident that the corresponding explanations are always applicable to multiple, in particular all, wheel carriers connected to the axle carrier.

[0004] The wheel of the motor vehicle is rotatably mounted on the wheel carrier, in particular in a wheel bearing arranged or fastened to the wheel carrier. The wheel carrier is connected via at least one control arm, but preferably via a plurality of control arms. The control arm or each of the control arms engages the wheel carrier on the one hand and the axle carrier on the other. The control arm or at least one of the control arms engages one of the bearing points of the axle carrier. One of the bearing points is arranged on the first longitudinal member and another of the bearing points on the second longitudinal member, preferably opposite one another. In the latter case, the bearing points are therefore arranged at the same positions on the longitudinal members.

[0005] The two longitudinal members can extend at least approximately in the main direction of travel of the motor vehicle. For example, they are arranged at least approximately or exactly parallel to one another. For example, they are arranged and / or formed mirror-symmetrically with respect to a longitudinal center axis of the axle carrier, wherein the longitudinal center axis can be parallel to the main direction of travel or coincide with it. The two longitudinal members, namely the first longitudinal member and the second longitudinal member, are connected to one another, preferably rigidly, via the at least one cross member. Particularly preferably, a plurality of spaced-apart cross members are provided, wherein each of the cross members connects the two longitudinal members to one another. The cross members are, for example, at least approximately perpendicular to the main direction of travel of the motor vehicle or the longitudinal center axis of the axle carrier.The cross members are preferably arranged spaced apart from one another in the axial direction with respect to the longitudinal center axis.

[0006] From the prior art, for example, the document DE 199 09 945 C1 is known, which is considered to be generic. This describes a subframe for a motor vehicle, in particular for a rear axle of a motor vehicle, which consists of a frame that can be attached to the vehicle body and which comprises at least cross members connected to longitudinal members. Bearings for wheel guide members are provided on the longitudinal members, and a transmission assembly is mounted in the frame between the longitudinal and cross members. The longitudinal member structure on each side comprises two supports arranged one above the other, which have a through-opening for axle shafts of the transmission assembly between them and converge approximately at the ends and are connected to the cross members. The transmission assembly is connected to the cross members and longitudinal members via a three-point bearing, and the axle shafts of the assembly extend through the through-opening towards the wheel.

[0007] Furthermore, the document DE 602 16 034 T2 is known from the prior art.

[0008] The object of the invention is to propose an axle carrier for a multi-track motor vehicle which has advantages over known axle carriers, in particular has improved collision behavior.

[0009] This is achieved according to the invention with an axle support having the features of claim 1. It is provided that the offset region transitions into one of the support regions via at least one bend, wherein at least one stiffness-reducing wall opening is formed in the wall of a support profile of the respective longitudinal support in the bend. It is fundamentally provided that the bearing points are each arranged in a bearing connection region of the corresponding longitudinal support, in which the longitudinal support has a lower stiffness perpendicular to its longitudinal extent than away from the bearing connection region.

[0010] Each of the bearing points is therefore located in one of several bearing connection areas. Each of the bearing connection areas is assigned to one of the longitudinal members, i.e., either the first longitudinal member or the second longitudinal member. In other words, each of the longitudinal members has at least one bearing connection area, in which a bearing point for one of several control arms is arranged, with a wheel carrier for a wheel of the motor vehicle being articulated or articulated via each of the control arms. In the context of this description, one of the bearing points will always be discussed below. However, the corresponding explanations are transferable to other bearing points of the axle carrier.

[0011] In the event of a collision between a motor vehicle and an obstacle, particularly a head-on collision with little transverse overlap, the wheel carrier and therefore the wheel of the motor vehicle may be deflected laterally, resulting in the wheel penetrating the passenger compartment of the vehicle. The lateral deflection is caused, for example, by a connection of the wheel carrier to the axle carrier via an additional link, around whose connection point on the axle carrier the wheel carrier is rotated together with the additional link in the event of a collision. To prevent this, it may be provided, for example, to release the connection between the axle carrier and the additional link in the event of a collision. A corresponding device may be provided for this purpose.

[0012] However, because it is fundamentally undesirable for components to detach from one another in the event of a collision, which would weaken the structure of the vehicle on the one hand, and on the other hand have free ends - in this case a free end of the additional control arm, which increases the risk of injury - a special design of the bearing connection area should be provided, in which the bearing point for the linkage of the control arm is located. For example, the wheel carrier is connected to the axle carrier via both the control arm and the additional control arm, in particular each is pivotally connected. This means that both the control arm and the additional control arm are pivotally connected to the wheel carrier on the one hand, and pivotally connected to the axle carrier on the other.

[0013] The control arm is arranged, for example, axially behind the additional control arm relative to the longitudinal center axis of the axle carrier in the main direction of travel. The additional control arm engages both the wheel carrier and the axle carrier further forward than the control arm in the main direction of travel. However, the control arm and the additional control arm can be located in the same plane, in particular in the same horizontal plane, i.e., in the vertical direction. For example, the control arm and the additional control arm are arranged below or above at least one other control arm, via which the wheel carrier is also connected to the axle carrier.

[0014] The bearing connection area, in which the bearing point for the control arm is arranged, should now have a lower rigidity perpendicular to its longitudinal extent, which preferably runs parallel to the longitudinal center axis of the axle carrier, than away from or outside the bearing connection area. The longitudinal member can therefore be deflected laterally in the bearing connection area relatively easily, in particular laterally outwards. In the event of a collision in which the longitudinal member having the bearing connection area is subjected to an axial force, the bearing connection area will deform laterally outwards, so that the distance between the wheel carrier and the corresponding longitudinal member or the axle carrier itself increases. Due to the deformability of the bearing connection area, the longitudinal member is compressed by the force while the bearing connection area is simultaneously deflected outwards in the axial direction.

[0015] Accordingly, any inward rotation of the wheel is counteracted, so that it is at most displaced axially in the direction away from the obstacle or even rotated outward. Such an axle support design can significantly improve the collision behavior of the vehicle. In particular, the risk of injury to vehicle occupants is significantly reduced because the aforementioned penetration of the wheel into the passenger compartment is effectively prevented.

[0016] According to the invention, at least one of the bearing connection areas is provided as an outwardly deflected offset area of the respective longitudinal member. With respect to the longitudinal center axis of the axle member, the bearing connection area should therefore be located laterally further outward than another area of the corresponding longitudinal member. The offset area is accordingly arranged offset with respect to other areas of the longitudinal member, in particular with respect to areas directly adjacent to it. The deflection of the offset area creates a desired deformation area that facilitates the deformation of the longitudinal member in the bearing connection area perpendicular to the longitudinal extent of the longitudinal member and, at the same time, a compression of the longitudinal member in the axial direction that causes the deformation.

[0017] A further development of the invention provides that the offset region has two legs and a curve connecting the two legs. The two legs are arranged symmetrically to one another, for example. Each of the legs can, on the one hand, lead into the corresponding longitudinal member away from the bearing connection area and, on the other hand, into the curve. Preferably, both legs run continuously into the curve. The curve can be symmetrical, analogous to the two legs, so that the arrangement of the two legs and the curve is symmetrical overall, in particular axially symmetrical when viewed from above onto the longitudinal member or the axle support.

[0018] Within the scope of a further preferred embodiment of the invention, it is provided that the bearing point is arranged at an apex of the offset region, in particular the curvature. The bearing point is thus assigned to the offset region and is located at its apex. The apex is understood, for example, to be the point in the offset region that is deflected the furthest in the lateral direction.

[0019] The apex represents the point of the offset range at which the derivative of the distance of the offset range from the longitudinal center axis of the axle carrier over the position in the axial direction is zero. The above conditions are met in particular if the bearing point is assigned to the curvature or is located at the apex of the curvature.

[0020] A further embodiment of the invention provides that the imaginary longitudinal central axes of the legs intersect each other at an obtuse angle. Each of the legs has such a longitudinal central axis.

[0021] These either intersect directly or at least lie in imaginary planes that intersect each other. The longitudinal center axes or the planes should enclose a specific angle with each other. This angle is particularly preferably obtuse, i.e., greater than 90°. Such a configuration enables easy deformation of the bearing connection area. Alternatively, it can of course be provided that a right angle or an acute angle exists between the longitudinal center axes or the planes. For example, an angle of 60° to 120°, 70° to 110°, or 80° to 100° is provided.

[0022] A further preferred embodiment of the invention provides that the respective bearing point is located below or above a support profile, in particular a hollow support profile, of the longitudinal member forming the offset region. The articulation of the control arm to the bearing connection region of the longitudinal member is thus offset with respect to the longitudinal member, in particular with respect to its longitudinal center axis, namely in the installed position of the axle carrier in the vertical direction. The bearing point is accordingly located below or above the longitudinal member or the support profile forming the longitudinal member. The support profile can, for example, be made of solid material. However, the support profile is particularly preferably in the form of a hollow support profile in order to achieve a weight-reduced design of the axle carrier.

[0023] According to the invention, the offset region transitions into, in particular, aligned, support regions of the longitudinal member at two spaced-apart connection points. The support regions are thus provided on both sides of the offset region. One of the support regions adjoins the offset region on a first side, and another of the support regions adjoins the offset region on a second side opposite the first side.

[0024] The support areas thus enclose the offset area between them. The transition between the offset area and the support areas occurs at the connection points. While the support areas can of course be arranged offset from one another, in particular parallel to one another, an aligned arrangement of the support areas is preferred. This means that the longitudinal center axes of the support areas coincide with one another, i.e., they lie one inside the other. With this design, a high rigidity of the axle carrier in the axial direction is achieved.

[0025] In a particularly preferred embodiment of the invention, at least one of the support regions, in particular both support regions, is straight, at least on the side facing the offset region. The straight design of the support regions serves to increase the rigidity of the axle support in the axial direction. Particularly preferably, the support regions are designed to be straight throughout. However, this applies at least on the side facing the offset region. For example, the entire straight region of the respective longitudinal member adjoining the offset region is referred to as the support region.

[0026] Furthermore, within the scope of the invention, the offset region transitions into one of the support regions via at least one bend, wherein at least one stiffness-reducing wall opening is formed in the wall of the support profile in the bend. Of course, it is advantageous if this applies to both support regions, so that the offset region transitions into the support regions via bends, wherein the stiffness-reducing wall opening is present in at least one of the bends, preferably in both bends.

[0027] The wall opening is formed in the wall of the support profile and preferably extends completely through the wall or support profile. In the case of a solid profile, the wall opening can therefore extend through the entire support profile, whereas in the case of a hollow profile, for example, it only extends through the wall of the support profile on one side of the support profile. Of course, a total of several wall openings can be provided in the bend(s), which are spaced apart from one another in the circumferential direction in the support profile.

[0028] For example, the wall opening is provided for the side of the support profile. The wall opening is located on the side of the support profile facing the longitudinal center axis of the axle support or the side of the support profile facing away from it. The wall opening is arranged in such a way that it reduces the rigidity of the longitudinal support or the bearing connection area, so that the bearing connection area can be deflected laterally more easily than is the case for the longitudinal support away from the bearing connection area.

[0029] Additionally or alternatively, it can be provided that the wall opening has larger dimensions in the circumferential direction of the support profile than in the longitudinal direction. The wall opening is in this respect in the form of a slot or an elongated hole. In order to achieve only the simple deflection of the bearing connection area in the lateral direction, but not to weaken the axial rigidity of the axle support, the dimensions of the wall opening are larger in the circumferential direction of the support profile than in its longitudinal direction. For example, the wall opening is provided at one of the connection points. Particularly preferably, each of the connection points is assigned such a wall opening. There can also be several wall openings per connection point, in particular diametrically opposite one another on the support profile.

[0030] Finally, a further preferred embodiment of the invention provides that at least one mounting point for an assembly mount and / or for a body is formed or arranged on at least one of the support regions. The assembly mount or the body can thus engage at the mounting point. The assembly mount is provided, for example, for supporting a drive unit of the motor vehicle, for example an internal combustion engine. Particularly preferably, the axle carrier has a plurality of such mounting points, with one mounting point being provided, for example, on each of the longitudinal members. In addition, one or more further mounting points can be provided on the cross member or at least one of the cross members.

[0031] The invention naturally also relates to a motor vehicle with an axle carrier, which can be designed according to the above statements. Regarding advantageous embodiments of the axle carrier, reference is made to the corresponding statements.

[0032] The invention will be explained in more detail below with reference to the exemplary embodiments shown in the drawings, without limiting the invention. In the drawings: Fig. 1 is a schematic representation of an area of a motor vehicle, namely an area of an axle carrier with a wheel connected to the axle carrier via a wheel carrier, wherein a configuration of the axle carrier before a collision is shown, Fig. 2 a schematic representation of the axle carrier according to the Fig. 1 in a configuration after a collision, and Fig. 3 another representation of the axle carrier with a control arm hinged to it for connecting the wheel carrier.

[0033] The Fig. 1 shows a schematic representation of an area of a motor vehicle 1, namely an axle carrier 2, on which a wheel 3 of the motor vehicle 1 is suspended. A first longitudinal member 4 of the axle carrier 2 is shown here. In addition to the first longitudinal member 4, the axle carrier 2 has a further, not shown here, second longitudinal member 5. The two longitudinal members 4 and 5 are connected to one another via a cross member 6, likewise not shown. The longitudinal member 4 has a bearing point 7, to which a control arm 8 is articulated, in particular pivotably. The control arm 8 serves to connect a wheel carrier (not visible here), in which the wheel 3 of the motor vehicle 1 is rotatably mounted. In addition to the control arm 8, a further control arm 9 is provided, via which the wheel carrier is also connected to the axle carrier 2, in particular the longitudinal member 4.For example, the link 9 engages further forward on the longitudinal member 4 in the main direction of travel of the motor vehicle 1 indicated by the arrow 10 than the link 8.

[0034] The bearing point is arranged in a bearing connection area 11 of the longitudinal member 4. In the bearing connection area 11, the longitudinal member 4 has a lower rigidity perpendicular to its longitudinal extent, i.e., preferably perpendicular to the main direction of travel indicated by arrow 10, than away from the bearing connection area 11. For this purpose, the bearing connection area 11 is designed as a laterally deflected offset area. It is clearly visible that the offset area is deflected outward in the laterally direction, i.e., in the direction of the wheel carrier or wheel 3.

[0035] For example, the offset region 11 has two legs 12 and 13 that are connected to one another, for example, via a bend 14 not shown here. The bearing point 7 is arranged at an apex 15 of the bearing connection region 11. In particular, the bearing point 7 is located between the two legs 12 and 13 or at a connection point between the two legs 12 and 13. The two legs 12 and 13, or the longitudinal center axes of the legs 12 and 13, meet at a specific angle. In the exemplary embodiment shown here, this angle is a right angle. However, an obtuse angle, i.e., an angle greater than 90°, is preferred.

[0036] Away from the bearing connection area 11, the longitudinal member 4 has support areas 16 and 17. These are preferably aligned with one another so that their longitudinal center axes coincide. The support areas 16 and 17 are particularly preferably straight, in particular continuously straight. The support areas 16 and 17 accommodate the bearing connection area 11 between them, which in turn merges into the support areas 16 and 17 at connection points 18 and 19. For example, the bearing connection area is connected to the support area 16 via connection point 18 on the one hand and to the support area 17 via connection point 19 on the other. For example, the further link 9 engages the support area 16.

[0037] The Fig. 2 shows a schematic representation of the area of the motor vehicle 1 after a collision, in which a force directed counter to the main direction of travel (arrow 10), indicated by arrow 20, acts on the wheel 3 or the wheel carrier. This causes a rotational movement of the wheel 3, which, if the control arm 8 is normally connected to the longitudinal member 4, can result in the wheel 3 penetrating a passenger compartment of the motor vehicle 1. This is prevented by the special design of the bearing connection area 11. This design enables the bearing point 7 to deflect laterally outwards when a force acts on the longitudinal member 4 as a result of the collision, so that the control arm 8 moves away from the longitudinal member 4 or at least the support areas 16 and 17.Accordingly, wheel 3 rotates, but this rotation is not directed around a bearing point of the control arm 9 on the longitudinal member 4, but rather around an axis of rotation present in the area of wheel 3. Overall, the collision displaces wheel 3 opposite to the main direction of travel 10, without wheel 3 coming excessively close to the axle carrier 2.

[0038] This results from the longitudinal member 4 being subjected to the force acting during the collision in the axial direction. The force is introduced, for example, via the support area 16 into the bearing connection area 11. Due to the deformability of the bearing connection area 11, the force causes the longitudinal member 4 to compress in the axial direction, which in turn deforms the bearing connection area 11 in the lateral direction and thus deflects or pushes the bearing point 7 outwards. The force therefore shifts the connection points 18 and 19 towards one another in the axial direction, so that after the force has been introduced or the bearing connection area 11 has been deformed or the longitudinal member 4 has been compressed, they are spaced apart from one another in the axial direction by a smaller distance than before. The connection points 18 and 19 are therefore shifted towards one another during the deformation of the bearing connection area 11.

[0039] The Fig.3 shows a further schematic representation of the axle carrier 2 and the control arms 8 and 9. It is clear that the axle carrier 2 is constructed essentially symmetrically with respect to its longitudinal center axis 21. In this respect, partially similar elements are provided with the same reference numerals. The statements regarding one of the elements can be transferred to the other of the elements. It can be seen that the two longitudinal members 4 and 5 are rigidly connected to one another via the cross member 6. In addition to the cross member 6, a further cross member 22 is provided. The longitudinal members 4 and 5 are also rigidly connected to one another via this cross member. In the exemplary embodiment shown here, the cross members 6 and 22 are connected to one another via a web 23, so that they can also be regarded as a common cross member.

[0040] At least one mounting point 24 for an assembly mount or for a body is formed or arranged on at least one of the support areas 16 and 17, in the exemplary embodiment shown here on both support areas 16 and 17. In the present exemplary embodiment, the mounting point 24 arranged in the support area 16 is provided for the assembly mount, and the mounting point 24 located in the support area 17 is provided for the body. Additional mounting points 25 for the assembly mount can be provided, for example, on the cross member 22.

[0041] It can be seen that the bearing connection area 11 transitions into the support areas 16 and 17 via bends 26 and 27. The bends 26 and 27 are provided to create a continuous transition. Furthermore, it can be seen that at least one wall opening, preferably several wall openings 28, are formed in each of the bends 26 and 27. The at least one wall opening 28 extends through the wall of a support profile forming the bearing connection area 11 or the longitudinal beam 4, which is particularly preferably designed as a hollow beam profile.

[0042] The design of the motor vehicle 1 or the axle carrier 2 shown here enables a particularly advantageous behavior of the axle carrier 2 or the wheel 3 during or upon a collision of the motor vehicle 1 with an obstacle.

Claims

[1] Axle support (2) for a multi-track motor vehicle (1), comprising a first longitudinal member (4), a second longitudinal member (5) and at least one cross member (6, 22) connecting the first longitudinal member (4) and the second longitudinal member (5), wherein at least one link (8) for connecting a wheel carrier for a wheel (3) of the motor vehicle (1) is articulated to bearing points (7) of the first longitudinal member (4) and the second longitudinal member (5), wherein the bearing points (7) are each arranged in a bearing connection region (11) of the corresponding longitudinal member (4, 5), in which the longitudinal member (4, 5) has a lower rigidity perpendicular to its longitudinal extent than away from the bearing connection region (11), wherein at least one of the bearing connection regions (11) is present as an outwardly deflected offset region of the respective longitudinal member (4, 5), and wherein the offset region is provided at two spaced-apart connection points (18,19) into supporting areas (16,17) of the longitudinal member (4,5), , characterized by that the offset region merges into one of the support regions (16, 17) via at least one bend (26, 27), wherein in the bend (26, 27) at least one stiffness-reducing wall opening (28) is formed in the wall of a support profile of the respective longitudinal member (4, 5). [2] Axle carrier (2) according to claim 1, characterized by that the offset region has two legs (12,13) and a curvature (14) connecting the two legs (12,13) to one another. [3] Axle carrier (2) according to one of the preceding claims, characterized by that the bearing point (7) is arranged at an apex (15) of the offset area. [4] Axle carrier (2) according to claim 2, characterized by that imaginary longitudinal central axes of the legs (12,13) intersect each other at an obtuse angle. [5] Axle carrier (2) according to claim 3 or 4, characterized bythat the respective bearing point (7) is located below or above a support profile of the longitudinal member (4,5) forming the offset area. [6] Axle carrier (2) according to one of the preceding claims, characterized by that at least one of the support areas (16,17) is straight at least on its side facing the offset area. [7] Axle carrier (2) according to one of the preceding claims, characterized by that at least one mounting point (24, 25) for an assembly bearing and / or for a body is formed or arranged on at least one of the support areas (16, 17). [8] Motor vehicle with an axle carrier (2) according to one of claims 1 to 7.

Images