WO2013110528A1 - Subframe for a motor vehicle - Google Patents

Description

 Subframe for a motor vehicle Description

The invention relates to a subframe for a motor vehicle, comprising two longitudinal members, each with a trained for coupling to a vehicle body

Fixing portion, a first cross member which is fixed to the longitudinal beams and connecting them in the vehicle transverse direction, and a second cross member which is arranged parallel to the first cross member.

Such a subframe is known from DE 10 2006 058 993 A1. The second cross member of this subframe is split longitudinally and composed of two shell elements. In this case, the two shell elements form opposite bearing receiving sections, between which a bearing of a wheel guide element is arranged. Furthermore, one of the shell elements of the second cross member has two more, for coupling to a

Vehicle body formed mounting portions.

Another subframe with two side rails and two cross beams is known from DE 199 22 800 A1. One of the cross member is connected via two light metal casting node elements with the side rails. In this node elements are in each case a plurality of receptacles for Radführungsglieder and a receptacle for a bearing element for connecting the

Subframe integrated with the vehicle body. Further receptacles for bearing elements for connecting the subframe to the vehicle body are located on the longitudinal members, which extend for this purpose through the other cross member.

Further auxiliary frames are known from DE 30 48 754 A1, DE 33 40 973 A1, DE 101 20 934, EP 1 591 348 A1, DE 10 2005 045 295 A1, DE 10 2007 018 167 A1 and WO 201 1/032631 A1.

Against this background, the object of the invention is to provide alternatives

show conventional subframe constructions.

In particular, the invention aims to provide a subframe for a motor vehicle, which is characterized by high rigidity and strength and a low component weight and can be manufactured inexpensively. In this respect, the subframe known from DE 10 2006 058 993 A1 appears to be in need of improvement, especially with respect to the stiffness properties.

In the known from DE 199 22 800 A1 subframe results, if it would be made of steel, a relatively high component weight. This is counteracted in DE 199 22 800 A1 by the use of light metal or plastic, which, however, leads to relatively high material costs.

The above object is achieved by a subframe according to claim 1. The subframe according to the invention comprises two longitudinal members each having a fastening portion designed for coupling to a vehicle body, a first cross member which is attached to the longitudinal members and connects them in the vehicle transverse direction, and a second cross member which is arranged parallel to the first cross member. According to the invention, this further comprises two brackets, which are each attached to the front side on one of the longitudinal members and in each case on the second cross member to the second cross member to the

Attach side rails, with each console one or more for coupling

Radführungsgliedern has trained mounting portions and the brackets are each formed as sheet metal forming part.

This avoids the inherent disadvantages of the prior art discussed above.

The subframe according to the invention allows an increase in rigidity and strength at a reduced total weight.

Through the integrated brackets, the wall thicknesses of the individual components of the subframe can be adjusted to the required degree, so that there is an optimal material utilization.

The interface structure according to the invention takes into account in particular those from

Radführung originating forces, which via suitable Radführungsglieder in the

Subframe are initiated, and the power flow in the direction of vehicle body.

In contrast to DE 199 22 800 A1, the subframe can be made in steel, which offers significant cost advantages. Preferably, at least the side members, the second cross member and the brackets are made of steel. Advantageous embodiments in the invention are specified in further claims.

Preferably, the second cross member has two attachment portions formed for coupling to a vehicle body. Due to the arrangement of the body side

Attachment sections on the second cross member may be the console on which the

Radführungsglieder attack, are executed in terms of stiffness and strength with less weight, as if in addition the body-side mounting portions would be integrated, since the latter require a different directional stiffening due to the direction of the force application.

According to an advantageous embodiment, each console when viewed in the vertical direction to the mounting position of the subframe on a C-shape with two legs and a connecting these legs middle section. The C-shape is one of each

Vehicle longitudinal center axis open to the outside. This allows a stable and

Space-saving articulation of the wheel guide links on the consoles.

Preferably, a protruding from the central portion wing is pivoted between the legs. This supports the legs against each other, whereby the console is additionally stiffened without much effort. This is especially with regard to

Support the Radführungskräfte advantage.

According to a further advantageous embodiment of the invention, a sheet metal tab is disposed between the legs and connected thereto. The sheet metal tab is arranged so that it braces the console in the longitudinal direction of each engaging longitudinal member.

As a result, a further gain in stiffness is achieved, which can be used to reduce the wall thickness of the console and thus their weight.

The sheet metal tab can be designed as a separate insert sheet, which is welded between the legs. According to an advantageous embodiment, the sheet metal tab is formed by a wall portion which is issued from the leg, which lies opposite the respective side member. This wall section is at its free end with the

longitudinal beam side leg welded. A separate sheet metal element is not required in this case. According to a further advantageous embodiment of the invention, the subframe on a main extension plane, which is spanned by the side members and cross member. Each console has a first and a second attachment portion for coupling a respective Radführungsglieds, wherein with respect to the mounting position of the subframe, the first attachment portion above the main extension plane and the second

Attachment section is arranged below the main extension plane. The integration of multiple mounting portions for wheel guide in the console is compared to conventional solutions in which for each connection point a separate console is welded to a sheet metal construction, the manufacturing and assembly costs are reduced.

With the same aim, you can add one to each console if needed

Stabilizer bearing receptacle are formed, since the relevant forces of the

Console structure can be collected without additional effort in terms of component weight.

According to a further advantageous embodiment of the invention, bushes for receiving rubber-metal bearings for acoustically decoupled connection of the subframe to the attachment sections formed for coupling to the vehicle body to the

Vehicle body or sleeves for rigid connection of the subframe attached to the vehicle body.

According to a further advantageous embodiment of the invention, the front ends of the longitudinal members are connected to the brackets 14. This allows a favorable

Wall thickness adjustment in the connection area.

Preferably, the brackets are each arranged between the front end of a longitudinal member and the second cross member. In particular, the longitudinal members may each be fastened with a front end to a console, but not be connected directly to the second cross member. This allows a particularly favorable

Wanddickenabstimmung and thus a low total weight.

The subframe according to the invention is particularly suitable for multi-link rear axles, wherein preferably the second cross member is in the forward direction of travel in front of the first cross member. In principle, however, a reverse installation is possible. Furthermore, a

According to the invention subframe are also used on a front axle. In the following the invention will be described with reference to the drawing

Embodiments explained in more detail. The drawing shows in:

Figure 1 is a perspective view of a first embodiment of a

 inventive subframe obliquely from the front;

Figure 2 is a perspective view of the subframe according to the first embodiment from the rear bottom;

Figure 3 is an exploded view of the subframe;

Figure 4 is a first detail view of a console of the subframe seen from the inside;

Figure 5 is a second detail view of the console seen from the outside;

Figure 6 is a perspective view of a modification of the console; and in

Figure 7 is a partial spatial view of a second embodiment of a

 Subframe invention seen from the side.

The first embodiment shows a subframe 10 for the rear axle of a

Passenger vehicle. However, the following can be explained

Also apply construction principles to the front axle subframe.

The subframe 10 includes two longitudinal beams 1 1, which extend in the vehicle longitudinal direction and are formed as bent tubular elements. Furthermore, the subframe 10 comprises two cross members, namely a first cross member 12, which is attached to the two longitudinal beams 1 1 and connects them in the vehicle transverse direction with each other, and a second cross member 13, which also extends in the vehicle transverse direction and is arranged parallel to the first cross member 12 ,

In the illustrated embodiment, the second cross member 13 is arranged with respect to the forward direction V in front of the first cross member 12. Both cross members 12 and 13 are composed of two shell elements 12a, 12b, 13a, 13b, which as Blechumformteile, preferably made of sheet steel, are formed. The shell elements 12a, 12b, 13a, 13b are interconnected by welding or riveting, for example. The respective division plane extends in the vertical direction and in the vehicle transverse direction. The second cross member 13 forms a longitudinally split hollow profile body, while the first cross member 12 is open at the bottom.

The subframe 10 further comprises two brackets 14, which each connect a longitudinal member 1 1 with the front second cross member 13. The brackets 14 are attached to the front side of the respective side member 1 1, which extends to the rear shell member 13a of the second cross member 13 forward.

The front ends of the side members 1 1 are connected to the brackets 14. The brackets 14 are each arranged between the front end of a longitudinal member 1 1 and the second cross member 13. Preferably, the longitudinal members 1 1 are each attached to a front end to a console 14, but not directly connected to the second cross member. This allows a particularly favorable wall thickness adjustment and thus a low total weight.

Preferably, the front ends of the side members terminate with respect to the

Vehicle longitudinal direction approximately at the height of the rear wall of the second cross member 13. The brackets 14 are used in the profile of the second cross member 13. The outlet of the side members 1 1 is guided so that this would meet in straight continuation in the longitudinal direction of the second cross member 13.

As can be seen in particular Figure 3, the rear shell member 13a of the second cross member 13 in the vehicle transverse direction is shorter than the front shell member 13b, so that end portions 13c of the front shell member 13b project laterally beyond the rear shell member 13a. The brackets 14 are arranged in the vehicle transverse direction at the front end on the rear shell element 13a and secured thereto, for example, welded. Further, the brackets 14 are located rearward of the end portions 13c of the front tray member 13b with respect to the forward traveling direction V, being in

Forward travel direction V are supported at the end portions 13c and are preferably welded thereto.

Each of the consoles 14 has the shape of a "C" open to the installation position of the subframe 10 when viewed in the vertical direction from the vehicle longitudinal center axis X to the outside. In particular, each console 14 has a front leg 14a forward in the forward direction of travel V, a second rear wheel 14 with respect to the forward direction of travel V.

Leg 14b and one of these two legs 14a and 14b connecting central portion 14c. The brackets 14 are in this case made as a sheet metal forming part each of a sheet metal blank, preferably made of sheet steel, so that they have a substantially constant wall thickness.

On the brackets 14 are each two mounting portions 14d, 14e formed for coupling of wheel guide not shown. These attachment portions 14d, 14e are, as can be seen in particular Figures 1 and 2, on opposite sides of a main extension plane of the subframe 10, which is spanned by the side members 1 1 and the cross member 12 and 13. In the illustrated embodiment, the attachment portions 14d and 14e are formed by wall portions of the legs 14a and 14b which have suitable openings for attachment of corresponding link bearings. The mounting portions 14 and 14e are accessible from the side, so that the arm bearings can be used without great effort between the legs 14a and 14b and secured, for example by means of through-bolts. However, depending on the manner of connection of the Radführungsglieder the mounting portions 14d and 14e may be configured differently.

As can be seen in particular from FIG. 4, one of the fastening sections 14d lies clearly above the main extension plane of the auxiliary frame 10. It is also slightly offset relative to the longitudinal member 11 to the outside of the auxiliary frame 10. For additional stiffening of this upper mounting portion 14 d is a wing 14 f, the

Continuing substantially perpendicular central portion 14c of the console 14, pivoted between the legs 14a and 14b and accordingly angled to the central portion 14c. The wing 14f is supported on the legs 14a and 14b and is fixed thereto, for example welded with its side edges to the legs 14a and 14b.

At the below the main extension plane of the subframe 10 further attachment portion 14e such a stiffening is not made, but also possible.

Furthermore, in the illustrated embodiment on each console 14 a

Stabilizer bearing receptacle 14g formed. This can be clearly seen in Figure 3 on the back outside of the lying in the forward direction V rear second leg 14b. to Connection of a stabilizer bearing, not shown here serves as an example a planar wall section with one or more openings on the rear lying second leg 14b, which is located below the associated longitudinal member 1 1. Depending on the design of the stabilizer bearing, the stabilizer bearing receptacle 14g on the second leg 14b can also be designed differently. A support of a stabilizer, if one is needed at all, but can also elsewhere on the subframe 10 or on

Vehicle structure done.

Between the legs 14a and 14b, a sheet metal tab 15 is also arranged, which braces the corresponding bracket 14 in the longitudinal direction of the respective engaging longitudinal member 1 1. The sheet metal tab 15 is inserted at the level of the end face of the longitudinal member 1 1 between the legs 14a and 14b and connected in the illustrated embodiment of Figure 5 with the inner sides of the legs 14a and 14b, preferably welded. In this case, the sheet metal tab 15 extends obliquely downwardly from the upper attachment portion 14d and outwardly to the lower attachment portion 14e. She concludes with the

Vehicle vertical direction an angle in the range of preferably 5 to 60 degrees, and more preferably from 15 to 40 degrees.

As shown particularly in FIG. 3, the first leg 14a can be provided with wall recesses 14h for weight reduction, with a correspondingly angled web 14i remaining for the support of the sheet metal tab 15.

In the first embodiment, the sheet metal tab 15 is a separate component, which may have a different wall thickness than the console 14.

However, it is also possible to form the sheet metal tab 15 by a wall portion 14j made up of the first leg 14a, as shown in FIG. The wall section 14j is disengaged from the first leg 14a except for a connecting edge 14k and bent inward along the connecting edge 14k in the direction of the second leg 14b. The free end 141 of the wall portion 14j abuts against the inside of the longitudinal member side second leg 14b and is preferably attached thereto, for example, welded.

The above-described embodiment of the brackets 14 in sheet metal construction allows a stiffness and strength-optimized design with respect to the male Radführungskräfte with minimal component weight and low production costs. For fixing the subframe 10 on the vehicle body, a total of four correspondingly formed fastening portions 11a and 13d are provided. From this there are two at the rear end portions of the two side members 1 1 and two at the ends of the front second cross member 13. As can be seen in Figure 1, the

Attachment portions 13d of the second cross member 13 are disposed on the cantilevered end portions 13c of the front shell member 13b and protrude laterally beyond the brackets 14.

If the auxiliary frame 10 is acoustically decoupled connected to the vehicle body, are attached to the mounting portions 1 1 a and 13 d rubber-metal bearings, of which in the figures, only the associated sockets 16 are shown. The sockets 16 are attached to the mounting portions 1 1 a and 13d, for example by welding.

Finally, two brake hose holder 17 are attached to the subframe 10.

The subframe 10 thus consists of eight sheet metal parts (12a, 12b, 13a, 13b, twice 14 and twice 15), two bending tubes (twice 1 1), four bushes (16) and two brake hose holders (twice 17), which preferably together by welding are connected.

Figure 7 shows a second embodiment, which differs from the first embodiment only by the configuration of the side member 1 1 and the attachment to

Vehicle structure different.

Instead of tubular elements come here components with an open profile cross section as a longitudinal member 1 1 'are used. The illustrated side members 1 1 'have a C-shaped profile cross-section, wherein the open side of the profile is directed away from the Fahrzeuglängsmittelachse X away to the outside. The longitudinal members 1 1 'can be designed as in DE 10 2006 058 993 A1 and connected to the brackets 14'.

The superimposed side edges 1 1 b 'of the C-shaped profile of the side members 1 1' may optionally be stiffened by a sleeve 18 'arranged between these, through which at the same time in conjunction with suitable clamping bolt a rigid connection of the subframe 10' takes place on the vehicle body. The sleeves 18 'are either on the

concerned longitudinal beams 1 1 'attached or used loosely during assembly on the vehicle body. A rigid attachment of the front cross member 13 'on the vehicle body in the same way via sleeves 16', which are inserted between the profile flanks of the front shell member 13b '.

The rigid attachment of the subframe to the vehicle body shown in Figure 7 is also possible in the first embodiment.

Further, it is possible to connect the longitudinal beams 1 1 'shown in Figure 7 with an open profile cross section rubber-metal bearings on the vehicle body.

Furthermore, suitable positioning projections can be formed for positioning the end faces of the side members 11 or 11 'on the second legs 14b of the brackets 14, as described in DE 10 2006 058 993 A1.

The longitudinal members 1 1 and 1 1 'extend from the brackets 14 initially substantially or predominantly parallel to the rear, then each outwardly from each other

wegzukrümmen. The first cross member 12 is preferably arranged in the parallel region of the longitudinal members 1 1 and 1 1 'immediately before or in the region of the curvature to the outside.

On the first cross member 12 are also bearing points 12c for Radführungsglieder. These bearings 12c are arranged in the illustrated embodiment in a central portion and serve to connect a downwardly pivotable handlebar. For this purpose, the first cross member 12 is formed as a downwardly at least partially open profile, wherein mutually opposite profile edges each form a bearing receiving portion and a bearing of a Radführungslenkers is arranged between these bearing receiving portions.

As already stated, the first cross member 12 as a longitudinally divided component of two

Shell elements 12a and 12b composed, wherein the dividing plane perpendicular to the longitudinal members 1 1 and 1 1 'in the vertical direction. However, a one-piece design is also possible. The same applies to the second cross member 13th

The above-explained subframe 10 and 10 'are characterized by a high rigidity and strength with low component weight. You can also manufacture cost-effectively. The structure shown allows an optimal design of the wall thicknesses of the individual parts and thus a minimal use of materials. In addition, the available space is optimally utilized.

The invention has been explained in more detail above with reference to preferred embodiments. However, it is not limited to these embodiments, but includes all embodiments defined by the claims.

LIST OF REFERENCE NUMBERS

10, 10 'subframe

 1 1, 1 1 'side member

 1 1 a for attachment to the vehicle body trained mounting portion

12, 12 'first cross member

 12a shell element

 12b shell element

 12c bearings

 13, 13 'second cross member

 13a shell element

 13b shell element

 13c end section

 13 for coupling to the vehicle body trained mounting portion

14, 14 'console

 14a first leg

 14b second leg

 14c middle section

 14d for coupling a wheel guide member formed fastening portion

14e for coupling a wheel guide member formed fastening portion

14f wing

 14g stabilizer bearing mount

 14h wall recess

 14i footbridge

 14j wall section

 14k connecting edge

 141 free end

 15, 15 'tin plate

 16 bushing for rubber metal bearings

 17 brake hose holder

 18 'sleeve

 V forward direction

 X vehicle longitudinal center axis

Claims

claims 1 . Subframe for a motor vehicle, comprising:  two longitudinal members (1 1) each having a fastening portion (11a) designed for coupling to a vehicle body,  a first cross member (12) which is fixed to the longitudinal members (1 1) and connecting them in the vehicle transverse direction, and  a second cross member (13) disposed parallel to the first cross member (12), characterized by  two brackets (14), each of which is attached to one of the side members (1 1) and to the second cross member (13) to secure the second cross member (13) to the side members (1 1), each console (1) 14) one or more to  Having coupling of Radführungsgliedern trained mounting portions (14d, 14e), and  the brackets (14) are each formed as sheet metal forming part. Second subframe according to claim 1, characterized in that the second cross member (13) has two attachment portions (13d) formed for coupling to a vehicle body. 3. subframe according to claim 1 or 2, characterized in that each console (14) when viewed in the vertical direction to the mounting position of the subframe (10) has a C-shape with two legs (14a, 14b) and a central portion connecting these (14c) and the C-shape is open to the outside from a vehicle longitudinal center axis (X), respectively 4. subframe according to claim 3, characterized in that one of the  Central portion (14c) protruding wing (14f) between the legs (14a, 14b) is pivoted and this bracing the console (14) against each supported. 5. subframe according to claim 3 or 4, characterized in that a sheet metal tab (15) between the legs (14a, 14b) is arranged and connected thereto, and brackets the console in the longitudinal direction of each engaging longitudinal member. 6. subframe according to claim 5, characterized in that the sheet metal tab (15 ') by a from the respective side member (1 1) opposite leg (14 a) exhibited wall portion (14 j) is formed, which at its free end (141) the longitudinal beam side leg (14b) is welded. 7. subframe according to one of claims 1 to 6, characterized in that the subframe (10) has a main extension plane which is spanned by the longitudinal members (1 1) and cross member (12, 13) and each console (14) has a first and a second attachment portion (14d, 14e) for coupling one each  Radführungsglieds, wherein with respect to the installation position of the subframe (10) of the first mounting portion (14d) above the main plane of extension and the second mounting portion (14e) is arranged below the main plane of extension. 8. subframe according to one of claims 1 to 7, characterized in that on each bracket (14) has a stabilizer bearing receptacle (14g) is formed. 9. subframe according to one of claims 1 to 8, characterized in that formed on the coupling to the vehicle body mounting portions (1 1 a, 13 d) sockets (16) for receiving rubber-metal bearings for decoupled connection of the subframe (10) the vehicle body or sleeves (18 ') for rigid connection of the subframe (10') are attached to the vehicle body. 10. subframe according to one of claims 1 to 9, characterized in that the  Side members (1 1) are each connected with a front end to one of the brackets (14). 1 1. Subframe according to one of claims 1 to 10, characterized in that the brackets (14) in each case between the front end of a longitudinal member (1 1) and the second cross member (13) are arranged 12 subframe according to one of claims 1 to 1 1, characterized in that the longitudinal members (1 1) each attached to a front end to a bracket (14), but not to the second cross member (13) are connected. 13. Subframe according to one of claims 1 to 13, characterized in that at least the longitudinal members (1 1), the second cross member (13) and the brackets are made of steel. 14. Multi-link axle, comprising a subframe according to one of claims 1 to 13. 15. Multi-link axle in the form of a motor vehicle rear axle according to claim 14, characterized in that the second cross member (13) in the forward direction of travel in front of the first cross member (12).