초록 ▼

A rear region of a motor vehicle has an underbody with at least one air-guiding element that is adjustable from a rest position into various operative positions. One operative position increases negative lift and another operative position reduces aerodynamic drag. The air-guiding element is adjusta

A rear region of a motor vehicle has an underbody with at least one air-guiding element that is adjustable from a rest position into various operative positions. One operative position increases negative lift and another operative position reduces aerodynamic drag. The air-guiding element is adjustable into the individual operative positions via a central, transversely arranged pivot axis.

대표청구항 ▼

1. A motor vehicle with a vehicle rear, a rear wheel and an underbody or an underbody covering extending to the vehicle rear, the underbody or the underbody covering rising toward the vehicle rear to define a diffuser, the diffuser having a front end rearward of the rear wheel and a rear end at the

1. A motor vehicle with a vehicle rear, a rear wheel and an underbody or an underbody covering extending to the vehicle rear, the underbody or the underbody covering rising toward the vehicle rear to define a diffuser, the diffuser having a front end rearward of the rear wheel and a rear end at the vehicle rear and defining a diffuser length extending from the front end to the rear end of the diffuser, the motor vehicle comprising: at least one adjustable air-guiding element having a front edge spaced rearward of the front end of the diffuser by a distance at least equal to one-half the diffuser length and a rear edge in proximity to the vehicle rear and substantially adjacent the underbody or the underbody covering, and a holding and adjustment device connected to the air-guiding element and being configured for extending the air-guiding element from an upper rest position substantially adjacent the diffuser down toward a ground contact area on which the vehicle is supported, the holding and adjustment device further being configured for moving the air guiding element into a plurality of operative positions by pivoting the air-guiding element about an axis of rotation arranged substantially in a center of the air-guiding element and running transverse to a direction of travel. 2. The motor vehicle of claim 1, wherein the air-guiding element is movable via the holding and adjustment device from the rest position bearing against the underbody vertically down into a first of the operative positions, in which the air-guiding element is substantially parallel to and spaced from the underbody. 3. The motor vehicle of claim 2, wherein the air-guiding element is pivotable about the axis of rotation from the downwardly extended first operative position into a second of the operative positions, in which the air-guiding element is at an angle to the underbody and the front edge of the air-guiding element substantially bears against the underbody. 4. The motor vehicle of claim 3, wherein the air-guiding element is adjustable in at least one third operative position that is pivotable between the first operative position and the second operative position. 5. The motor vehicle of claim 1, wherein the underbody or the underbody covering rises from a rear axle of the motor vehicle substantially to a lower edge of the vehicle rear and forms the rear diffuser with a diffuser angle of approximately ≧25° formed between the underbody and a horizontal. 6. The motor vehicle of claim 1, wherein a distance from the front edge to the rear edge of the air-guiding element is approximately ⅓ to ½ of the length of the diffuser. 7. The motor vehicle of claim 1, wherein the rear edge of the air-guiding element is substantially flush with a lower edge of the vehicle rear. 8. The motor vehicle of claim 1, wherein the air-guiding element extends over an entire width between the rear wheels of the vehicle. 9. The motor vehicle of claim 1, wherein the air-guiding element has a wing profile with a convex lower surface and an upper surface that is nestable with the underbody covering. 10. The motor vehicle of claim 1, wherein the rear diffuser has longitudinal channels on the underbody and the at least one air-guiding elements comprises plural air-guiding elements disposed respectively in the longitudinal channels on the underbody and being adjustable about a transverse axis within the longitudinal channel. 11. The motor vehicle of claim 1, further comprising a control element that is operable to control movement of the air-guiding element into the individual operative positions and intermediate positions depending on a driving state of the vehicle.