Powered four-link rear axle for a motor vehicle

Abstract

A driven four-link rear axle (1) for a motor vehicle, comprising: a wheel carrier (2), a longitudinal control arm (3), an upper control arm (4) and two lower control arms (5, 6) for supporting the wheel carrier (2) on the vehicle body side, a driveshaft (7) for transmitting a drive torque to a vehicle wheel (8) rotatably mounted on the wheel carrier (2), and a vibration damper (9), wherein the vibration damper (9) engages the wheel carrier (2) below the wheel center (M) and extends in front of the driveshaft (7) and between one of the front lower control arms (5) and the upper control arm (4) in the direction of travel (F) inclined to a body-side mounting point (DO), wherein in the rest position the corresponding angle of inclination to the vertical (V) in the direction of travel (F) is in the range of 20° to 60° and the body-side mounting point (DO) of the vibration damper (9) is located within the height of the vehicle wheel (8) is characterized by,that the wheel-side mounting point (DU) of the vibration damper (9) on the wheel carrier (2) is further away from a longitudinal center axis of the vehicle in the transverse direction (Q) than the wheel-side mounting point (S2) of the front lower control arm (5) on the wheel carrier (2), in that the vibration damper (9) with its wheel-side mounting point (DU) engages the wheel carrier (2) inside a rim of the vehicle wheel (8) in the direction of travel (F) in front of the wheel center (M), whereas the wheel-side mounting point (S2) of the front lower control arm (5) lies outside the rim of the vehicle wheel (8).

Description

[0001] The invention relates to a driven four-link rear axle for a motor vehicle, comprising a wheel carrier, a longitudinal control arm, an upper control arm and two lower control arms for supporting the wheel carrier on the vehicle body side, a driveshaft for transmitting a drive torque to a vehicle wheel rotatably mounted on the wheel carrier and a vibration damper.

[0002] Such a driven four-link rear axle is known from DE 10 2010 021 215 A1. Based on this, the invention aims to achieve a greater loading width on a motor vehicle while maintaining the axle principle of a driven four-link rear axle.

[0003] Four-link rear axles are already well-known in various designs for vehicles with non-driven rear axles. However, with a driven rear axle, the problem arises of accommodating the driveshaft required for the drive within the wheel suspension area, meaning that wheel suspension configurations for non-driven rear axles are generally unsuitable for driven rear axles.

[0004] The aforementioned problem is solved by a driven four-link rear axle according to claim 1. The driven four-link rear axle according to the invention is characterized in particular by the fact that the vibration damper engages the wheel carrier below and in front of the wheel center in the direction of travel and runs inclined in the direction of travel in front of the driveshaft and between one of the lower control arms and the upper control arm towards a body-side point of application, wherein in the rest position the angle of inclination to the vertical in the direction of travel is in the range of 20° to 60° and the body-side connection point of the vibration damper is located within the height of the vehicle wheel.

[0005] This allows all components for supporting and driving the vehicle wheel to be arranged below a loading floor in a passenger vehicle, resulting in a particularly large loading width and thus a larger trunk volume in a motor vehicle compared to conventional damper arrangements.

[0006] Nevertheless, collisions between the wheel-guiding control arms on the one hand and the vibration damper and the drive shaft on the other hand are avoided when the corresponding rear axle wheel compresses and rebounds.

[0007] Furthermore, the inclination of the vibration damper promotes a progressive damping ratio, i.e., a damping ratio that increases with increasing suspension travel. Accordingly, the effect of the vibration damper increases over the suspension travel.

[0008] The direct connection of the vibration damper to the wheel carrier allows, compared to DE 10 2010 021 215 A1, a larger and therefore better travel ratio, resulting in better responsiveness and improved comfort.

[0009] Specific embodiments of the invention are the subject of further patent claims.

[0010] For example, the vibration damper can be coupled laterally, i.e., on the outside of the vehicle, to a longitudinal member of the vehicle body via its body-side mounting point. This allows for space-saving installation and easy mounting.

[0011] Furthermore, the body-side connection point of the vibration damper can be located below the height of the vehicle floor, so that the loading width is not affected by the vibration damper.

[0012] According to a further embodiment of the invention, the vibration damper has a wheel-side mounting point which is arranged within a rim of the vehicle wheel. This allows for a relatively large axial length of the vibration damper with corresponding damping capacity.

[0013] In this sense, the wheel-side mounting point of the vibration damper can also be coupled lower on the wheel carrier in relation to the vertical direction than a wheel-side mounting point of the front lower control arm.

[0014] Furthermore, the vibration damper can be inclined inwards in the transverse direction of the vehicle, whereby in the installation rest position the inclination angle to the vertical in the transverse direction of the vehicle is in a range of 20° to 30°, resulting in a particularly favorable utilization of the available installation space.

[0015] According to another embodiment of the invention, the vibration damper can be inclined more strongly in the direction of travel than in the transverse direction of the vehicle.

[0016] Furthermore, it is possible to position the wheel-side attachment point of the front lower control arm outside the rim of the vehicle wheel, thus providing more space inside the rim for the vibration damper.

[0017] With regard to improved lateral and longitudinal force steering, it is also advantageous to position the vehicle body-side attachment point of the front lower control arm in the direction of travel in front of its attachment point on the wheel carrier.

[0018] The invention will now be explained in more detail with reference to an embodiment illustrated in the drawing. The drawing shows: Fig. 1 a spatial view of an embodiment for a driven four-link rear axle of a motor vehicle Fig.2 a side view of the rear axle according to Fig. 1 to illustrate the alignment of the vibration damper, Fig. 3 a side view of the rear axle according to Fig. 1 to illustrate the position of a virtual steering axis, Fig. 4 a top view of the rear axle according to Fig. 1, and in Fig. 5 a rear view of the rear axle according to Fig. 1.

[0019] The figures illustrate an example of a driven four-link rear axle. 1 for a passenger vehicle.

[0020] The driven four-link rear axle 1 Each wheel side includes a wheel carrier as a component. 2 , a longitudinal control arm 3 , an upper control arm 4 , a front lower wishbone 5 and a rear lower wishbone 6 for supporting the wheel carrier on the vehicle body 2Furthermore, a driveshaft 7 for transmitting a drive torque to a component attached to the wheel carrier 2 rotatably mounted vehicle wheel 8 as well as a vibration damper 9 planned.

[0021] The trailing arm 3 , which is predominantly in the direction of travel F The path is elastic, achieved by means of a rubber-metal bearing. 10 coupled to a vehicle body, so that the longitudinal control arm 3 to achieve a direction that is essentially transverse to the vehicle Q The longitudinal control arm can pivot. 3 rigidly attached to the bike rack 2 coupled, shown here by way of example using two screws. However, it is also possible to make an elastic coupling at this point using two rubber-metal bearings, or alternatively the wheel carrier. 2 one piece with the longitudinal control arm 3 to train.

[0022] The upper control arm 4is in the direction of travel F and above the center of the vehicle wheel 7 , in the following wheel center M , to the bike rack 2 and a support frame 11 the vehicle body is coupled to it. The coupling can be made on both sides via rubber-elastic bearings. Preferably, the connection point is located O2 on the bike rack 2 in the direction of travel F slightly before the connection point O1 on the vehicle body, in this case subframe 11 , in order to enable improved lateral force steering.

[0023] Furthermore, the wheel-side connection point is located O2 above a lower end section of the direction of travel F inclined vibration damper 9 A shifting of the wheel-side attachment point O2 on the bike rack 2 It is not possible in the direction of travel, as otherwise the upper control arm would be damaged. 4 during the compression and rebound of the vehicle wheel8 with the vibration damper 9 would result in a collision, which must be avoided.

[0024] The upper control arm 4 The embodiment is characterized by the passage past a longitudinal beam. 12 of the vehicle body with a crank 13 provided which are located under the longitudinal beam 12 through. By the crank of the wishbone 4 Since it remains confined to one plane, it can be used uniformly for both the left and right sides of the vehicle. This keeps manufacturing and assembly costs low. However, due to the driveshaft 6 the on-board connection point O1 of the upper control arm 4 no further against the direction of travel F be postponed.

[0025] In a variation of the exemplary embodiment, a two-dimensionally cranked upper control arm is used. 4for use, whose on-board connection point O1 in the direction of travel behind the driveshaft 7 This allows for further improved lateral force steering.

[0026] The front lower wishbone 5 is in the direction of travel F in front of and below the wheel center M to the bike rack 2 coupled. Preferably, the coupling is elastic, for example by means of a rubber-metal bearing. The corresponding wheel-side connection point S2 preferably lies outside the rim of the vehicle wheel 8 Furthermore, the front lower control arm 5 to the vehicle body, preferably the subframe attached to it 11 coupled. Preferably, the coupling is also elastic here, for example by means of a rubber-metal bearing.

[0027] The on-board connection point S1 of the front lower wishbone 5is preferably located in the direction of travel F seen in front of the wheel-side attachment point S2 to enable improved lateral steering in the sense of a toe-in effect under lateral and longitudinal steering forces. In particular, an angle of attack to the vehicle's transverse direction can be achieved in a stationary installation position in the FQ plane. Q It is designed to be in the range of 5° to 30°. Furthermore, the front lower wishbone runs... 5 preferably essentially horizontal.

[0028] The front lower wishbone 5 can be used in particular as a rod-shaped steering linkage or tie rod with exactly one wheel-side attachment point. S2 and exactly one on-board connection point S1 must be executed.

[0029] The rear lower control arm 6 is in the direction of travel F behind and below the wheel center M to the bike rack 2coupled. The corresponding wheel-side connection point is marked U4 in the figures. Similarly, the rear lower wishbone is 6 in the direction of travel F behind and below the wheel center on the vehicle body, in this case on the subframe 11 coupled. The corresponding attachment point on the body side is labeled U3 in the figures. The coupling can be elastic on both sides, for example again via a rubber-metal bearing.

[0030] How in particular Fig. The rear lower control arm can be seen from point 4. 6 in the direction of travel F behind the driveshaft 7 predominantly in the transverse direction of the vehicle Q .

[0031] The wheel-side attachment point U4 of the rear lower wishbone 6 viewed from the outside of the vehicle, it lies in the direction of travel Fseen preferably as close as possible to the attachment point on the body side U3 In particular, an angle of attack opposite to the vehicle's transverse direction can be achieved in a resting installation position in the FQ plane. Q It should be in the range of 5° to 10°.

[0032] In the illustrated embodiment, the rear lower control arm 6 designed as a spring link, which incorporates a suspension spring 14 supported. In this example, the latter is shown as a coil spring, which has a spring mount. 15 connects to the vehicle body. An additional spring can be located inside the coil spring. 16 It must be arranged to create a progressive wheel load curve. The spring mount 15 The additional spring also supports 16 on the vehicle body.

[0033] The vibration damper 9 engages below and in the direction of travel F in front of the wheel center M on the bike rack2 on. It runs in the direction of travel. F in front of the driveshaft 7 as well as between the front lower wishbone 5 and the upper control arm 4 through and in the direction of travel F inclined towards a structural point of attack DO In its resting installed position, the angle of inclination to the vertical lies in the direction of travel. F , i.e., in an FV plane, in the range of 20° to 60°. Furthermore, the body-side connection point is located there. DO of the vibration damper 9 within the height of the vehicle wheel 8 .

[0034] The vibration damper 9 is in the direction of travel F seen behind the front lower wishbone 4 to the bike rack 2 coupled. The corresponding lower connection point of the vibration damper. 9 is in the characters with YOU This is designated. It lies in the direction of travel. Fseen in front of and below the wheel center M in an area within the rim of the vehicle wheel 8 .

[0035] The wheel-side attachment point YOU of the vibration damper 9 is in relation to the vertical direction V lower on the wheel carrier 2 arranges itself as the wheel-side attachment point S2 of the front lower wishbone 4 .

[0036] The point lies in the transverse direction of the vehicle. YOU further away from a vehicle's longitudinal center axis than the point S2 .

[0037] The coupling of the vibration damper 9 on the bike rack 2 This is preferably done elastically.

[0038] As already mentioned, the vibration damper is in the direction of travel. F seen tilted obliquely forwards. Furthermore, as in Fig. 5. Clearly visible, an additional inclination in the transverse direction of the vehicle. QIt should be directed towards the center of the vehicle. In particular, it is possible that the corresponding angle of inclination to the vertical V in the transverse direction of the vehicle Q , i.e. in the QV plane, in a range of 20 to 30°.

[0039] Preferably, the vibration damper 9 stronger in the direction of travel F as in the vehicle transverse direction Q inclined.

[0040] The on-board connection point DO of the vibration damper 9 It is preferably elastically mounted and located in an area below the tire's upper surface. In other words, the body-side attachment point... DO of the vibration damper 9 is the installation rest position of the rear axle 1 in relation to the vertical direction V in an area within the height of the vehicle wheel 8 arranged.

[0041] The body-side connection of the vibration damper 9preferably takes place below the level of a vehicle floor and preferably on the outside of the longitudinal beam. 12 .

[0042] Due to the location of the body-side connection point DO or a corresponding bearing laterally, namely on the outside of the vehicle on the longitudinal beam 12 is a fastening, for example screwing from the outside at screw points 17 a damper bearing can be replaced in a simple way.

[0043] So that, as a result of the damping forces during compression, the vehicle wheel 8 The damper axle is designed so that the wheel is not pushed towards toe-out, which would result in undesirable oversteer in the handling. A , which are connected via the body-side and wheel-side attachment points DO and YOU of the vibration damper 9 runs, aligned in such a way that its extension lies behind the wheel contact point RAhits the roadway. This point of impact is in Fig. 2 with DA The wheel contact point. RA It is located vertically below the wheel center without any caster. M . The wheel contact point of a moving motor vehicle can RA as a result of the tire trail when moving in the direction of travel F Shift it slightly backwards. The point of impact is also located there in this case. DA in the direction of travel F seen from behind the wheel contact point RA .

[0044] This means that if one also considers the inclination of the vibration damper 9 in the transverse direction of the vehicle Q includes those in the Fig. 2 and Fig. 4 distances shown EAR and AY of the point of impact DA from the wheel contact point RA in the direction of travel F as well as in the transverse direction of the vehicle Q in all compression and rebound states of the rear axle1 Each always has and retains the same sign.

[0045] Regarding the upper control arm 4 is the vibration damper 9 in the direction of travel F in front of the upper wishbone 4 arranged. The wheel-side attachment point O2 of the upper control arm 4 When viewed in the QF plane, it lies approximately above the wheel-side attachment point. YOU of the vibration damper 9 or possibly slightly behind.

[0046] Furthermore, the drive shaft is located 7 in the direction of travel behind the vibration damper 9 and the upper control arm 4 .

[0047] A stabilizer 18 can be done, for example, by means of a connecting rod 19 directly attached to the bike rack 2 It must be coupled. It runs from its coupling point to the connecting rod. 19 first in the direction of travel Fforwards and then in the transverse direction of the vehicle Q angled. The stabilizer 18 is in a stabilizer bearing 20 recorded, which is located on the vehicle body, in this case on the subframe 11 is determined.

[0048] In one version, without limitation, a possible drive unit for driving the cardan shaft is included. 7 on the subframe 11 arranged, preferably elastically mounted on it. The drive unit can be, for example, an electric motor.

[0049] The four-link rear axle configuration described above results in a virtual, i.e., imaginary, steering axis. L , as they are in Fig. Figure 3 is shown. In this case, it always occurs behind the wheel contact point. RA at the point LA onto the roadway. This ensures that the vehicle wheel 8under the influence of lateral forces, it moves in the direction of toe-in. The position of the virtual steering axis LA This is primarily determined by the arrangement of the control arms. 4 , 5 and 6 determined. In contrast, the influence of the stiffness of the rubber-metal bearings used at the connection points of these handlebars recedes into the background.

[0050] The arrangement of the vibration damper described above 9 , in particular its inclination and the arrangement of the lower attachment point YOU as far away as possible from the vehicle's longitudinal center axis and preferably within the rim of the vehicle wheel 8 This results in a compact package without affecting the vehicle's ground clearance.

[0051] At the same time, this makes it possible to access the upper, body-side connection point. DO of the vibration damper 9to be positioned as close to the roadway as possible, thereby achieving a large loading width on the vehicle.

[0052] Moreover, the arrangement described above allows for a progressive damper ratio, i.e., the damper ratio decreases with increasing compression of the vehicle wheel in question. 8 This has the advantage that the effect of the vibration damper is also increased. 9 increases with increasing suspension travel.

[0053] The inclination of the vibration damper also promotes toe-in steering due to damping forces during compression.

[0054] The invention has been explained in more detail above with reference to various embodiments and further modifications. These serve to demonstrate the feasibility of the invention. Individual technical features, which were explained above in the context of other individual features, can also be implemented independently of these features and in combination with other individual features, even if this is not expressly described, as long as it is technically possible. The invention is therefore expressly not limited to the specifically described embodiments, but encompasses all configurations defined by the claims. 1 Four-link rear axle 2 bike carriers 3 trailing arms 4 upper control arm 5 front lower wishbone 6 rear lower wishbone 7 Cardan shaft 8 vehicle wheel 9 vibration dampers 10 rubber-metal bearings 11 Subframe (vehicle body) 12 longitudinal beams of the vehicle body 13. Goiter 14 Assembly spring 15 Spring mount 16 Additional spring 17 Screw point upper damper bearing 18 Stabilizer 19 Stabilizer link 20 stabilizer bearings A damper axle AX distance DA to RA in direction of travel F AY distance DA to RA in the transverse direction of the vehicle Q DA Impact point damper axle on roadway DO mounting point of the vibration damper DU wheel-side connection point of the vibration damper F Direction of travel (forward) L virtual (imaginary) steering axis LA point of impact of virtual steering axis on roadway M Wheel center O1 body-side attachment point of the upper control arm 4 O2 wheel-side attachment point of the upper control arm 4 Q Vehicle transverse direction RA Wheel contact point S1 body-side attachment point of the front lower wishbone 5 S2 wheel-side mounting point of the front lower wishbone 5 U3 body-side attachment point of the rear lower wishbone 6 U4 wheel-side attachment point of the rear lower wishbone 6 V Vertical direction QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102010021215 A1 [0002, 0008]

Claims

[1] Driven four-link rear axle (1) for a motor vehicle, comprising: a bike carrier (2), a longitudinal control arm (3), an upper control arm (4) and two lower control arms (5, 6) for supporting the wheel carrier (2) on the vehicle body side, a driveshaft (7) for transmitting a drive torque to a vehicle wheel (8) rotatably mounted on the wheel carrier (2), and a vibration damper (9), characterized by , that the vibration damper (9) engages the wheel carrier (2) below and in the direction of travel (F) in front of the wheel center (M) and runs in the direction of travel (F) in front of the drive shaft (7) and between one of the lower control arms (5) and the upper control arm (4) inclined towards a body-side point of application (DO), wherein in the installation rest position the corresponding angle of inclination to the vertical (V) in the direction of travel (F) is in the range of 20° to 60° and the body-side connection point (DO) of the vibration damper (9) is located within the height of the vehicle wheel (8). [2] Driven four-link rear axle (1) for a motor vehicle according to claim 1, characterized by , that the vibration damper (9) is coupled laterally, namely on the outside of the vehicle, to a longitudinal member (12) of a vehicle body with its body-side connection point (DO). [3] Driven four-link rear axle (1) for a motor vehicle according to claim 1 or 2, characterized by , that the body-side attachment point (DO) of the vibration damper (9) is located below a vehicle floor of the motor vehicle. [4] Driven four-link rear axle (1) for a motor vehicle according to any one of claims 1 to 3, characterized by , that the vibration damper (9) has a wheel-side attachment point (DU) which is located within a rim of the vehicle wheel (8). [5] Driven four-link rear axle (1) for a motor vehicle according to any one of claims 1 to 4, characterized by , that the wheel-side mounting point (DU) of the vibration damper (9) is coupled to the wheel carrier (2) at a lower position with respect to the vertical direction (V) than a wheel-side mounting point (S2) of the front lower control arm (5). [6] Driven four-link rear axle (1) for a motor vehicle according to any one of claims 1 to 5, characterized by, that the vibration damper (9) is inclined inwards in the transverse direction (Q) of the vehicle, wherein in the installation rest position the angle of inclination to the vertical (V) in the transverse direction (Q) of the vehicle is in a range of 20 to 30°. [7] Driven four-link rear axle (1) for a motor vehicle according to any one of claims 1 to 6, characterized by , that the vibration damper (9) is inclined more strongly in the direction of travel (F) than in the transverse direction of the vehicle (Q). [8] Driven four-link rear axle (1) for a motor vehicle according to any one of claims 1 to 7, characterized by , that the wheel-side attachment point (S2) of the front lower control arm (5) lies outside the rim of the vehicle wheel (8).

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