Disassembled McPherson strut suspension

Abstract

A McPherson strut suspension (10) in which a damper support (12) carrying a damper is mounted on a lower control arm (14) and in which a pivot bearing (16) is mounted on the damper support (12), wherein the pivot bearing (16) is pivotably mounted about a steering axis (22) oriented in the vehicle vertical direction (FH) relative to the damper support (12) via a first bearing (18) and a second bearing (22) arranged above it, viewed in the vehicle vertical direction (FH), characterized in that the second bearing (22) is arranged on the damper support (12) so as to be displaceable relative to the damper support (12) in the vehicle transverse direction (FQ).

Description

[0001] The invention relates to a dissolved McPherson wheel suspension according to the type specified in the preamble of claim 1.

[0002] McPherson strut suspensions are a widely used axle type due to their low complexity and low manufacturing costs, and are well known from the prior art. Reference is made to DE 43 40 557 A1 only as an example.

[0003] A McPherson strut suspension enabling camber adjustment is disclosed in US patent 7,793,956 B2. For this purpose, a rocker arm is provided which is mounted on the lower control arm via a pivot bearing on the control arm side about a first pivot axis oriented substantially in the longitudinal direction of the vehicle, and on the wheel carrier via a pivot bearing on the wheel carrier about a second pivot axis also oriented substantially in the longitudinal direction of the vehicle.

[0004] A well-known modified McPherson strut suspension is the so-called Revo-Knuckle design (see ATZ magazine 5 / 2004, Volume 106, pages 434 to 440). This defining design is characterized by the fact that the damper strut, mounted on a lower control arm, is divided into two parts: a spring-loaded section that carries the damper and a steering (swivel bearing) section mounted to it, which forms the new steering axis. To suppress rotation of the fixed damper strut around the original axis of rotation, the Revo-Knuckle design uses a special ball-and-socket joint (hinge joint) between the lower control arm and the damper strut instead of the lower ball joint.

[0005] The invention is based on the objective of further developing a dissolved McPherson wheel suspension according to the type specified in the preamble of claim 1 in such a way that it is possible to influence the camber.

[0006] This problem is solved by the features of the characterizing part of claim 1 in combination with its preamble features.

[0007] The dependent claims represent advantageous further developments of the invention.

[0008] In a known manner, in the dissolved McPherson wheel suspension, a damper support bearing is mounted on a lower control arm and a pivot bearing is mounted on the damper support bearing via a first bearing and a second bearing arranged above it, viewed in the vehicle's vertical direction (FH), pivoting about a steering axis that is essentially aligned in the vehicle's vertical direction.

[0009] According to the invention, the second bearing is arranged to be displaceable relative to the damper strut in the transverse direction (FQ) of the vehicle. The inventive design of the split McPherson wheel suspension proves to be particularly advantageous, since it now allows for camber adjustment similar to that of a double wishbone axle.

[0010] A preferred first embodiment of the split McPherson strut suspension provides that the second bearing is slidably mounted on the damper strut via a lever mechanism supported on the control arm. Mounting the second bearing via a lever mechanism supported on a control arm has the effect of providing a passive system that provides positive camber during compression and negative camber during rebound. A particular advantage of this embodiment is that it can be implemented very cost-effectively.

[0011] Preferably, the lever mechanism comprises a first lever arm rotatably mounted on the wishbone, a pivot joint connected to the lever arm and mounted on the damper strut, and a second lever arm connected to the pivot joint and the second bearing. Due to the lever mechanism's simple design, a particularly cost-effective construction is ensured.

[0012] According to an embodiment that requires little installation space, the second lever arm is guided through an opening in the damper leg.

[0013] Since the movement performed by the second lever arm is neither purely linear nor purely rotational, the second lever arm is preferably designed in the form of a rod-shaped elastomer bearing, which allows, in particular, movement in the transverse direction of the vehicle and also the necessary rotation about the vehicle's longitudinal axis. For this purpose, the elastomer bearing is stiff in the longitudinal direction and about the vehicle's vertical axis, and exhibits lower stiffness in the transverse direction compared to the longitudinal direction. Due to the high stiffness about the vehicle's vertical axis, it is also ensured that the elastomer bearing can absorb large moments about the vehicle's vertical axis. Such a bearing is known from DE 10 2016 003 683 A1. A particular advantage of the design of the second lever arm in the form of the described rod-shaped elastomer bearing is that, due to the described flexibility in the overall system, corresponding elastomer bearings, e.g.,The typical soft comfort bearing in the control arm, which runs lengthwise along the vehicle, can be omitted.

[0014] According to a second embodiment of the split McPherson strut suspension, the second bearing is mounted on the strut so as to be displaceable in the transverse direction of the vehicle via an actuator arranged on the strut. This embodiment proves advantageous because it now also allows for active adjustment of the camber in the split McPherson strut suspension.

[0015] Preferably, the actuator is designed as a piezoelectric actuator. The use of a piezoelectric actuator ensures, in particular, a fast response time at high force generation and wear-free operation.

[0016] Further advantages and application possibilities of the present invention will become apparent from the following description in conjunction with the embodiment shown in the drawing.

[0017] In the drawing, this means: Fig. 1 a McPherson strut suspension according to the invention, and Fig. 2 the wheel suspension Fig. 1 in the compressed state.

[0018] Fig. 1 and Fig. Figure 2 shows a schematic representation of a McPherson strut suspension, designated overall by the reference numeral 10.

[0019] The McPherson strut suspension 10 comprises a damper support 12, which carries a damper and is mounted on a lower control arm 14, and a pivot bearing 16 mounted on the damper support. The pivot bearing 16 is pivotally mounted about a steering axis 22 oriented essentially vertically via a first bearing 18, hereinafter also referred to as the lower bearing, and a second bearing 20, hereinafter also referred to as the upper bearing.

[0020] How Fig. 1 and Fig. As shown in section 2, the upper bearing 20 is displaceably mounted in the transverse direction FQ of the motor vehicle via a lever mechanism designated as a whole by the reference numeral 30 in relation to the damper shank 12.

[0021] For this purpose, the lever assembly 30 comprises a first lever arm 30-1 mounted on the control arm 14 and extending essentially in the vertical direction FH of the vehicle, a second lever arm 30-2 extending essentially in the transverse direction FQ of the vehicle and operatively connected to the upper bearing 20, and a pivot joint 30-3 mounted on the damper stanchion 12 and connecting the two lever arms 30-1 and 30-2.

[0022] Due to the mounting of the second bearing 20 via the lever assembly 30 supported on the wishbone 14, a camber gain is made possible in a simple way as with a double wishbone axle: How Fig.Figure 2 shows that the lifting mechanism 30 causes a positive camber when the suspension compresses. Conversely, a negative camber is set when the suspension rebounds.

[0023] The second lever arm 30-2, extending in the transverse direction FQ of the vehicle, is designed in the form of a rod-shaped elastomer bearing. This bearing exhibits high stiffness in the longitudinal direction FL of the vehicle, while allowing slight rotations about the longitudinal axis. It is more flexible in the transverse direction FQ, thus enabling a small displacement in this direction, and also exhibits high stiffness about the vertical axis of the vehicle, allowing it to absorb large moments. A corresponding elastomer bearing is described, for example, in DE 10 2016 003 683 A1.

Claims

[1] Disassembled McPherson wheel suspension (10) in which a damper support leg (12) carrying a damper is mounted on a lower control arm (14) and in which a pivot bearing (16) is mounted on the damper support leg (12), wherein the pivot bearing (16) is pivotally mounted about a steering axis (22) oriented in the vehicle vertical direction (FH) with respect to the damper support leg (12) via a first bearing (18) and a second bearing (22) arranged above it, viewed in the vehicle vertical direction (FH), characterized by , that the second bearing (22) is arranged to be displaceable relative to the damper shank (12) in the transverse direction (FQ) of the motor vehicle on the damper shank (12). [2] Disassembled McPherson wheel suspension (10) according to claim 1, characterized by , that the second bearing (20) is slidably mounted on the damper stem (12) via a lever mechanism (30) supported on the wishbone (14). [3] Disassembled McPherson wheel suspension (10) according to claim 2, characterized by, that the lever mechanism (30) has a first lever arm (30-1) mounted on the control arm (14), a pivot joint (30-3) connected to the first lever arm (30-1) and mounted on the damper leg (12), and a second lever arm (30-2) connected to the pivot joint (30-3) and the second bearing (20). [4] Disassembled McPherson wheel suspension (10) according to claim 3, characterized by , that the second lever arm (30-2) is guided through a hole in the damper leg (12). [5] Disassembled McPherson wheel suspension (10) according to claim 3 or 4, characterized by , that the second lever arm (30-2) is designed in the form of a rod-shaped elastomer bearing which is stiff in the longitudinal direction of the vehicle (FL) and about the vertical axis of the vehicle and which has a lower stiffness in the transverse direction of the vehicle (FQ) compared to the longitudinal direction of the vehicle (FL). [6] Disassembled McPherson wheel suspension (10) according to claim 1, characterized by, that the second bearing (20) is mounted on the damper shank (12) so as to be displaceable in the direction of the motor vehicle (FQ) via an actuator arranged on the damper shank (12). [7] Disassembled McPherson wheel suspension (10) according to claim 6, characterized by that the actuator is designed as a piezo actuator.

Images