Untitled record

The claims contained in this utility model were only submitted by the applicant after the search report had been served (Section 19 (4) GMG) and were therefore not the basis for the search report. The version of the claims on which the search report is based can be inspected at the Austrian Patent Office during office hours.

DVR 0078018

AT 009 506 U1

The invention relates to an output vane for a motor vehicle, the angle of attack of which is set as a function of the speed, which extends in the transverse direction of the vehicle and is movably connected to the vehicle body. Such output vanes are sometimes incorrectly referred to as “spoilers”, which, in contrast to an output vane, have the purpose of causing the flow to break away. Output vanes are usually only attached to competition vehicles or their imitations, either on the front and / or over the rear axle, depending on the driving dynamics requirements.

Output vanes only develop their effect when the flow is sufficiently fast and when the vehicle is moving at sufficient speed. The downforce increases disproportionately with speed, but is limited by the load capacity of the vehicle's tires. With increasing speed, however, the air resistance also increases, which consumes engine power or reduces the achievable speed. The downforce improves the vehicle's grip on the ground and is required above all when cornering, much less when driving straight ahead at very high speed. The output force is therefore only needed in the speed range in which medium-fast to fast corners are driven.

This problem is addressed in DE 103 20 865 A1 and a solution is proposed which does not require an externally controlled actuator. There, a wing that can be pivoted about a transverse axis against the force of a spring is combined with further wings, the air resistance of which causes the entire wing arrangement to pivot. As a result, the activated output vane should snap back into the no-lift position at a very high speed. How is not apparent from the description. In any case, a sudden transition from one position to the other would cause an unstable driving condition, which is not allowed.

It is therefore the object of the invention to create a technically feasible construction which ensures a smooth transition from the engaged position to the neutral position at a higher speed, the respective speed ranges being adaptable.

According to the invention, this is achieved in that the output vane is connected to the vehicle at two height-adjustable points that are spaced apart from one another in the longitudinal direction of the vehicle. The two points can also be on either side of the wing. Thus, the increase and decrease of the angle of attack are decoupled, the former takes place via one point, the latter via the other. As a result, the organs for the enlargement and for the reduction of the angle of attack can be designed in accordance with the driving dynamics requirements independently of one another.

The distribution of tasks is preferably such that a slider is provided that responds to the dynamic pressure and acts on the front of the two spaced-apart points in such a way that it is lowered when the dynamic pressure rises, the output vane being pivoted in the rear point (claim 2), and that the slide acts on the rear of the two spaced-apart points as the back pressure continues to rise, that this is also lowered (claim 3), whereby the angle of attack is reduced and the output force is smaller again.

Alternatively, the rear of the two spaced points can be supported on the vehicle by means of a spring, which spring allows a lowering of the point from a certain output force acting on the output vane, so that the angle of attack of the output vane and thus the downforce exerted by it decreases again (claim 4) .

In a further development of the invention, the rear of the two spaced-apart points, viewed in the longitudinal direction of the vehicle, essentially coincides with the point of application of the resulting output force (claim 5). So the two movements of the output wing are largely

AT 009 506 U1 decoupled. In the case of the alternative according to claim 4, this offers particular advantages.

Usually, output vanes are connected to the vehicle body on both sides. When using the invention, a pair of spaced-apart points are then provided on both sides. In a preferred embodiment, the output vane is arranged on the front of the motor vehicle and the two spaced points lie in the vertical longitudinal symmetry of the vehicle (claim 6). This simplifies the operation and leaves the aerodynamic design of the vehicle greater freedom.

A further refinement of the invention consists in that a damping element is arranged between the vehicle body and at least one of the points (claim 7). This can counteract the risk of aerodynamically excited vibrations.

The invention is described and explained below with reference to figures. They represent:

Fig. 1: A vehicle equipped with the device according to the invention in plan view,

Fig. 2: Detail II in Fig. 1, enlarged,

Fig. 3: A diagram of the device according to the invention in longitudinal section,

Fig. 4: An embodiment of the device according to the invention in longitudinal section,

Fig. 5: A diagram.

In FIG. 1, the vehicle is denoted as a whole by 1 and its vertical plane of symmetry is denoted by 4. The vehicle 1 has front wheels 2 and rear wheels 3. The output vane 5 according to the invention is attached to the front of the vehicle 1 here.

As can be seen in Fig. 2, the output vane 5 is slightly swept in plan view, its wing nose 6 and its trailing edge 7 are inclined backwards. The airflow 8 flows against the vehicle. As a result, when the output vane 5 is positioned negatively, an output force F occurs, see the indicated profile section. The locus of the output force acting over the extension of the wing is denoted by 9. The point of application of the resulting downforce 10 is thus obtained for the entire wing.

This point of application 10 is at the same time the first point at which the wing is supported in an articulated manner on the vehicle 1. A first pivot axis 11 passes through it in the transverse direction of the vehicle. The wing nose located in front of it is supported in an articulated manner on the vehicle at a second point 12. It is rotatably mounted there about a second pivot axis 13. The second point 12 is connected in a suitable manner to a slide 14 in the front of the vehicle, which is pushed backwards by the dynamic pressure of the incoming airstream against the force of a spring (21 in FIG. 3).

3 shows a diagram of the kinematics causing the change in the angle of attack 24. The slide 14 is displaceable in the longitudinal direction with respect to the vehicle 1 against the force of a first spring (and a first damper 22) and with it a first guide 20 on which a shoe 23 rides. If the slide 14 moves backwards, the shoe 23 is pulled downwards. The wing 5 pivots about the first axis 11, so that the angle of attack 24 increases. A second guide 26 is attached to the vehicle 1. A piston 27 is guided in it and is pressed upwards against a stop 28 of the second guide 26 by a second spring 29. A second damper is provided between the piston 27 and the vehicle 1 to prevent the wing from flapping. When the output force exerted by the wing is large enough to overcome the force of the second spring 29, the wing 5 presses the piston 27 downward against the force of the second spring 29, as a result of which the negative angle of attack 24 decreases. The wing pivots about the second pivot axis 13.

In an embodiment according to FIG. 4, the parts 20 to 30 corresponding to parts

AT 009 506 U1 is provided with the reference numerals 40 to 50. The difference is that the first pivot axis 11 pierces the piston and the second spring 49 surrounds the second damper 50. However, the invention also relates to all kinematic equivalents of the actuating devices described. Furthermore, instead of the slide 14, the entire front part of the vehicle can also be displaceable in the longitudinal direction of the vehicle. The output vane according to the invention can also be used as an output means acting on the rear wheels.

Fig. 6 also shows the relationship that can be achieved with the output vane according to the invention between the driving speed (more precisely: the speed of the flow encountering the vehicle), plotted on the ordinate and the output force, plotted on the abscissa, as a curve. Its first piece 51 lies on the ordinate axis as long as the dynamic pressure exerted on the slide 14 has not yet overcome the force of the first spring 21. The second section 52 of the curve begins at a speed V1 (for example 80 km / h) and shows a disproportionate increase in the downforce. At point 53, at a speed V2 (for example 200 km / h), the downforce exerted by the wing overcomes the force of the second spring 29 and the wing is pivoted towards a smaller angle of attack, corresponding to the third section 54 of the curve. It is advisable to reduce the angle of attack slowly and only slightly or to prevent it from increasing further. The shape of the curve 51, 52, 54 can be varied over a wide range by dimensioning and pretensioning the two springs 21, 29; the transition at 53 can also be designed to be soft or running, deviating from the diagram.