SUBFRAME FOR A VEHICLE

Description

[0001] The invention relates to a subframe for a vehicle according to the preamble of independent claims 1, 3 and 6.

[0002] In an electrified vehicle axle for a two-track vehicle, the drive unit can consist of an electric motor and a transmission, via which the electric motor drives the vehicle to flanged shafts leading to the vehicle wheels. The drive unit is supported in a three- or four-point bearing on a subframe. This, in turn, is mounted to the vehicle body via subframe bearings.

[0003] In a drive device of this type, the drive unit is supported on a longitudinal member or cross member of a subframe via at least one unit support. The longitudinal or cross member is designed as a hollow beam that defines a cavity closed in cross-section by a circumferential hollow beam wall.

[0004] In the current state of the art, bearing brackets are attached to such a subframe as separate components, to which the power unit support can be connected. This type of connection results in a high package density in the area of ​​the vehicle axle, with the brackets limiting the available installation space for the drive unit and increasing the component complexity during assembly of the vehicle axle. Furthermore, separate tools, additional production equipment, and production time are required to weld the brackets to the subframe.

[0005] The brackets can also weaken the fatigue strength of the subframe. Furthermore, the position of the brackets may have to be chosen in such a way that separate disassembly of the drive unit is no longer possible.

[0006] DE 102 35 110 A1 discloses a subframe for motor vehicles. DE 10 2013 007 473 A1 discloses a suspension device for drive units of motor vehicles. DE 10 2019 124 348 A1 discloses a mounting arrangement for a component on an axle carrier for a vehicle. Furthermore, EP 1 035 003 A2 discloses a subframe according to the preambles of claims 1, 3, and 6.

[0007] The object of the invention is to provide a subframe for a vehicle by means of which the package density and the component expenditure during assembly of the subframe can be reduced in a structurally simple manner.

[0008] The object is achieved by the features of the characterizing parts of claims 1, 3 and 6. Preferred developments of the invention are disclosed in the subclaims.

[0009] The invention is based on a subframe for a vehicle having an assembly mount. In the assembly mount, an assembly support is pivotably connected to an assembly mount on the subframe about a bearing axis. The assembly mount is axially attached on both sides to a bracket wing of a bearing bracket of the subframe. According to claim 1, the assembly mount is arranged in a space-saving manner in an inner corner region of the subframe, at which a first subframe support and a second subframe support converge. One of the bracket wings is formed directly by an inner side of the first subframe support. The other bracket wing, however, cannot be directly integrated into the subframe support, but rather can be designed as a separate bracket wing component that is connected to the second subframe support.In this way, the bearing bracket is provided with reduced installation space requirements and with reduced component expenditure.

[0010] The separate console wing component, which is connected to the second subframe support, can be spaced from the first subframe support by a bearing gap. The assembly mount is positioned in the bearing gap.

[0011] In a preferred embodiment, the first subframe support can be a subframe cross member, while the second subframe support is a subframe longitudinal member. The subframe cross member and the subframe longitudinal member converge at a corner node of the subframe. The assembly mount is located in the inner corner area of ​​this corner node.

[0012] In one technical implementation, the first subframe support, into which a console wing is directly integrated, can be designed as a hollow support that defines a cavity. The cavity is enclosed by a hollow support wall, viewed in the hollow support cross-section. Furthermore, the first subframe support has an access opening on the outer side of the hollow support wall, through which the assembly mount can be installed or removed.

[0013] The bearing axis of the assembly mount, around which the assembly support is pivotably articulated, can be defined by a bearing pin. This can be mounted axially on both sides of the assembly mount in the respective bracket wing of the bearing bracket. With a view to a compact and component-rigid bracket wing geometry, the bracket wing is designed as a U-profile part according to a further aspect of the invention. The U-profile part has a base wall in which the bearing pin is mounted, and support legs angled therefrom, which support the base wall relative to the subframe. The two support legs protrude axially outwards from the base wall. The bracket wing is connected to the subframe at its base wall bottom edge and / or at its support leg bottom edge. The connection is made by welding.

[0014] To ensure a compact and rigid design, the base wall is triangular in shape, with base wall edges that converge triangularly from the base wall bottom edge at a preferably rounded base wall apex. A bearing opening for the bearing pin is formed in the area of ​​the base wall apex.

[0015] In a specific design variant, the edge profile of the respective base wall edge can be divided into a transition edge, at which the respective support leg is angled away from the base wall, and a free edge that extends to the base wall apex.

[0016] A rigid connection of the console wing to the subframe is particularly important. For this purpose, at least one of the console wing's support legs can be extended with a tab. This tab can project beyond the base wall's bottom edge of the console wing. The base wall's bottom edge can be connected to one subframe side, while the support leg tab can be connected to another, differently oriented subframe side. For example, the base wall's bottom edge is connected to the inside of the frame, while the support leg tab is connected to the underside of the frame.

[0017] In the triangular geometry of the bearing bracket described above, the two support legs are not aligned parallel to each other, but rather converge toward the base wall apex. This results in a particularly compact and component-rigid bracket wing geometry. For ease of production, it is preferred if the bracket wing is realized as a sheet metal formed part, in which a flat sheet metal blank is first provided, which is then formed into the bracket wing in a cutting and forming operation.

[0018] According to a further aspect of the invention, the subframe support, i.e., a subframe cross member or a subframe longitudinal member, can be formed with a reduced cross-section and a trough-shaped mounting recess in which the console wings are arranged. In this way, occurring operating forces can be diverted from the subframe support via the subframe mount in a component-stable manner toward the subframe, utilizing the stability of the respective subframe support obtained with the aid of the trough-shaped mounting recess.

[0019] The subframe support is a hollow beam that defines a cavity that, viewed in the hollow beam cross-section, is closed by a hollow beam wall. The trough-shaped mounting recess is formed in the closed hollow beam wall. The hollow beam wall has a rectangular cross-section, with an upper horizontal hollow beam top wall and a lower horizontal hollow beam bottom wall connected at transition edges to vertical hollow beam side walls.

[0020] The trough-shaped mounting recess is positioned as follows: The contour of one of the two transition edges is interrupted by the trough-shaped mounting recess. In this case, a trough base of the mounting recess merges into the side wall and the floor or top wall of the subframe support at one edge of the recess.

[0021] This provides a particularly rigid support base for the bearing bracket on the subframe. The connection strength between the bracket wing and the subframe support can be further increased as follows: the base wall bottom edge of the bracket wing can be connected to the trough floor. In contrast, the support leg tab can overlap the trough edge of the mounting recess and be connected to the side wall and / or the bottom or top wall of the hollow support.

[0022] Embodiments of the invention are described below with reference to the attached figures.

[0023] They show: Fig. 1 shows a top view of a subframe for a vehicle with a drive unit mounted thereon; Figs. 2 to 4 show detailed views of the unit mountings on the subframe.

[0024] In the Figure 1An electrified vehicle axle for a two-track vehicle is indicated to the extent necessary for understanding the invention. The vehicle axle has Figure 1 a drive unit 1, which consists, for example, of an electric motor and a transmission. The drive unit 1 is connected in a three-point bearing to the top of a subframe 7 of the vehicle. The subframe 7 has in the Figure 1 two lateral subframe longitudinal members 9, which are connected at front and rear corner nodes to front and rear subframe cross members 11, 13. According to the Figure 1 At the corner areas of the subframe 9, bearing eyes 14 are formed for subframe bearings (not shown), via which the subframe 7 can be mounted to the vehicle body. On the outer sides of the vehicle, the two subframe longitudinal members 9 each have connection points 15 for chassis links (not shown).

[0025] In the Figure 1 The drive unit 1 is mounted on unit supports 17 of the drive unit 1 via two front unit bearings Q1, Q2 on the front subframe cross member 11 and via another unit bearing Q3 on the rear subframe cross member 13. The subframe cross members 11, 13 and the two subframe longitudinal members 9 are each designed as hollow beams, which form a cavity 18 ( Figure 2 ). This is closed by a surrounding rectangular hollow beam wall, as seen in the hollow beam cross-section. The hollow beam wall consists, as shown in the figures, of an upper, horizontal cover wall 19 ( Figure 4 ) and a lower, horizontal floor wall 21 ( Figure 3 ), which are connected to transition edges 22 ( Figure 3 and 4 ) with a vertical inner side wall 23 ( Figure 3 ) and a vertical outer side wall 24 ( Figure 2 ) are connected.

[0026] Each of the assembly bearings Q1, Q2, Q3 is designed as a rubber-metal sleeve bearing, which is only described in detail in the Figure 2 is shown. Accordingly, the rubber-metal sleeve bearing consists of a radially outer sleeve 25 and a radially inner, sleeve-shaped bearing core 27, between which a vibration-damping elastomer body 29 is arranged. A bearing pin 31 is guided through the bearing core 27 of the assembly bearings Q1, Q2, Q3, defining a bearing axis L about which an assembly support 17 of the drive assembly 1 is pivotally articulated. The bearing pin 31 is mounted axially on both sides of the assembly bearing Q1, Q2, Q3 in a bracket wing 35, 37 of a bearing bracket 39, which is connected to the subframe 7.

[0027] The bearing brackets 39 of the assembly mounts Q1, Q2, Q3 are implemented with different component geometries: For example, the assembly mount Q1, as shown in Figure 2, is arranged in an inner corner area of ​​the subframe 7, which is spanned between the front subframe cross member 11 and the subframe longitudinal member 9. On the assembly mount Q1, the bearing bracket 39 has a bracket wing 35 implemented as a separate bracket wing component, which is welded to the subframe longitudinal member 9. In contrast, the other bracket wing 37 is not implemented as a separate bracket wing component, but rather is a direct and integral part of the inner side wall 23 of the front subframe cross member 11. The two bracket wings 35, 37 are spaced from one another by a bearing gap 41, in which the assembly mount Q1 is arranged.An access opening 43 is formed on the outer side wall 24 of the front subframe cross member 11, through which the assembly bearing Q1 can be mounted / removed. According to the . Figure 2 The bearing pin 31 is guided through a pin hole 45 in the inner side wall 23 of the front subframe cross member 11 and supported with its pin head 47 on the opening edge area of ​​the pin hole 45. A weld nut 49 is welded to the console wing 35, to which the pin tip of the bearing pin 31 is screwed.

[0028] In the Figure 3The bearing bracket 39 of the assembly mount Q2 is shown. Accordingly, the two bracket wings 35, 37 are realized as separate bracket wing sheet metal parts, which are designed in a compact and component-rigid bracket wing geometry. Each of the two bracket wings 35, 37 is designed as a U-profile part, specifically with a base wall 51, in which the (not shown) bearing pin 31 is guided through a pin hole 52, and with support legs 53 angled therefrom, which support the base wall 51 on the inner side wall 23 of the subframe 7. The respective bracket wing 35, 37 is welded to the subframe 7 at its base wall bottom edge 55 and at its support leg bottom edge 57. As can be seen from the Figure 3As can be seen further, the base wall 51 is triangular in shape. Its base wall edges 59 converge triangularly from the base wall bottom edge 55 at a rounded base wall vertex 61, in the region of which the bolt hole 52 is formed. The edge profile of each base wall edge 59 is divided into a transition edge 63, at which the base wall 51 merges into the respective support legs 53, and a free edge 65, which extends to the base wall vertex 61.

[0029] In the Figure 3 The lower support legs 53 of the two bracket wings 35, 37 are each extended by a sheet metal tab 67, which projects beyond the base wall bottom edge 55 with a projection Δz. The base wall bottom edge 55 is according to the Figure 3welded to an inner side wall 23 of the front subframe cross member 11, while the support leg sheet metal tab 67 engages around the lower subframe transition edge 22 and is connected to the bottom wall 21 of the front subframe cross member 11.

[0030] As from the Figure 3 As can be seen further, the two support legs 53 of the console wing 35, 37 are not aligned parallel to each other, but rather are inclined toward each other. This enables a particularly compact and component-rigid console wing geometry.

[0031] In the Figure 4The connection of the subframe support 17 via the third subframe mount Q3 to the rear subframe cross member 13 is shown. Accordingly, the rear subframe cross member 13 has a trough-shaped mounting recess 71 in which the two console wings 35, 37 are arranged. The two console wings 35, 37 have approximately the same geometry as the two console wings 35, 37 of the subframe mount Q2.

[0032] The trough-shaped mounting recess 71 is formed in the hollow beam wall without opening the cavity 18 of the rear subframe cross member 13 to the outside. Figure 4As can be seen, the contour of the upper transition edge 22 of the rear subframe cross member 13 is interrupted by the trough-shaped mounting recess 71. A trough bottom 69 of the mounting recess 71 merges at a trough edge 73 into the inner side wall 23 and into the upper cover wall 19 of the rear subframe cross member 13. In addition, the two support legs 53 of the console wing 35, 37 are each extended by a support leg sheet metal tab 67, which engages over the trough edge 73 and is connected to the inner side wall 23 and the cover wall 19 of the rear subframe cross member 13. In contrast, the base wall bottom edge 55 of the console wing 35, 37 is welded to the trough bottom 69. LIST OF REFERENCE SYMBOLS:

[0033] 1 Drive unit 7 Subframe 9 Subframe longitudinal members 11, 13 Front and rear subframe cross members 14 Bearing eyes 15 Connection points 17 Unit support 18 Cavity 19 Top wall 21 Bottom wall 22 Transition edge 23 Inner side wall 24 Outer side wall 25 Outer sleeve 27 Bearing core 29 Elastomer body 31 Bearing bolt 35 Bracket wing 37 Bracket wing 39 Bearing bracket 41 Bearing gap 43 Access opening 45 Bolt hole 47 Bolt head 49 Weld nut 51 Base wall 52 Bolt hole 53 Support leg 55 Base wall bottom edge 57 Support leg bottom edge 59 Base wall edge 61 Base wall apex 63 Transition edge 65Free edge 67Support leg tab 69Trough bottom 71Mounting recess 73Trough edge Q1, Q2, Q3Aggregate bearing LBearing axis ΔzProtrusion

Claims

1. Subframe for a vehicle, having an assembly bearing arrangement in which an assembly support (17) is articulated on an assembly bearing (Q1) on the subframe (7) so as to be pivotable about a bearing axis (L), wherein the assembly bearing (Q1) is fastened axially on both sides to in each case one bracket wing (35, 37) of a bearing bracket (39) of the subframe (7), wherein the assembly bearing (Q1) is arranged in an inner corner region of the subframe (7) at which a first subframe member (11) and a second subframe member (9) converge, wherein one of the bracket wings (37) is formed directly by a wall of the first subframe member (11), wherein the first subframe member (11) is a hollow member which delimits a cavity (18) which, in a hollow-member cross section, is closed by means of a hollow-member wall, characterized in that the first subframe member (11) has on its frame-based outer side (24) an access opening (43) via which the assembly bearing (Q1) is able to be mounted / dismounted.

2. Subframe according to Claim 1, characterized in that the other bracket wing (35) is formed as a separate bracket-wing component which is attached to the second subframe member (9), and in that the bracket-wing component (35) is spaced apart from the first subframe member (11) via a bearing intermediate space (41) in which the assembly bearing (Q1) is arranged, and in that the first subframe member (11) is a subframe crossmember, and the second subframe member (9) is a subframe longitudinal member.

3. Subframe for a vehicle, having an assembly bearing arrangement in which an assembly support (17) is articulated on an assembly bearing (Q2) on the subframe (7) so as to be pivotable about a bearing axis (L), said bearing axis being defined by a bearing bolt (31) which, axially on both sides of the assembly bearing (Q2), is mounted in a bracket wing (35, 37) of a bearing bracket (39) of the subframe (7), wherein at least one of the bracket wings (35, 37) is formed as a U-shaped profile part with a base wall (51), in which the bearing bolt (31) is mounted, and with supporting legs (53) angled away therefrom, which support the base wall (51) with respect to the subframe (7), characterized in that the bracket wing (35, 37) is welded at its base-wall bottom edge (55) and at its supporting-leg bottom edge (57) to the subframe (7), and in that the base wall (51) is of triangular form, specifically with base-wall peripheral edges (59) which converge with a triangular shape at a preferably rounded base-wall apex (61), in the region of which a bearing opening (52) for the bearing bolt (31) is formed.

4. Subframe according to Claim 3, characterized in that at least one of the supporting legs (53) is extended by a tab (67) which projects beyond the base-wall bottom edge (55) with a projection (Δz), and in that the base-wall bottom edge (55) is attached to a frame inner side (23) of the subframe (7) and the supporting-leg tab (67) is attached to a frame top side (19) or frame bottom side (21).

5. Subframe according to either of Claims 3 and 4, characterized in that the two supporting legs (53) are not parallel to one another, but inclined towards one another in the direction of the base-wall apex (61), which results in a compact and component-rigid bracket-wing geometry, and / or in that the bracket wing (35, 37) is a formed sheet-metal part.

6. Subframe having an assembly bearing arrangement in which an assembly support (17) is articulated on an assembly bearing (Q3) on the subframe (7) so as to be pivotable about a bearing axis (L), said bearing axis being defined by a bearing bolt (31) which, axially on both sides of the assembly bearing (Q3), is mounted in a bracket wing (35, 37) of a bearing bracket (39) of the subframe (7), wherein a subframe member (9, 11, 13), that is to say a subframe crossmember or a subframe longitudinal member, is formed with a trough-shaped mounting depression (71), with cross-sectional reduction of the subframe member (9, 11, 13), in which mounting depression the bracket wings (35, 37) are arranged, wherein the subframe member (9, 11, 13) is a hollow member which delimits a cavity which, in a hollow-member cross section, is closed by means of a hollow-member wall in which the trough-shaped mounting depression (71) is formed, and wherein the hollow-member wall has a rectangular cross section in which an upper horizontal hollow-member top wall (19) and a lower horizontal hollow-member bottom wall (21) are connected at transition edges (22) to vertical hollow-member side walls (23, 24), characterized in that the contour profile of one of the transition edges (22) is interrupted by the trough-shaped mounting depression (71), and in that a trough bottom (69) of the mounting depression (71) transitions at a depression periphery (37) into the side wall (23, 24) and into the bottom wall or top wall (19, 21) of the subframe member (7).