STREAMLINING A.R DEFLECTOR FOR TRACTOR-TRAILER VEHICLE

An air deflector, which is adapted to be mounted on the roof of a cab of a tractor pulling a trailer and has a frontwardly facing totally curved air deflecting surface that is symmetrical about a vertical center plane and is forwardly convex in all horizontal and vertical cross-sectional planes, is disclosed. To define the deflecting surface, the deflector has a central portion and a pair of symmetrical rearwardly turned wing portions at the opposite sides of the central portion and includes a top edge of substantially circular curvature and a base edge of substantially elliptical curvature. The deflector is installed for angular adjustment about a horizontal axis to a number of different positions correlated with both the height difference between the tractor cab and trailer roofs and the distance between the rear of the cab and the front of the trailer, and so that the base edge of the deflector is located at a predetermined height above a given horizontal plane disposed below the plane of the cab roof and so that in all adjusted positions of the deflector the vertex of the included angle between the radii of curvature of the top and base edges of the deflector at the vertical center plane is located below the plane of the cab roof and on the said horizontal plane. This abstract is not to be taken either as a complete exposition or as a limitation of the present invention, however, the full nature and extent of the invention being discernible only by reference to and from the entire disclosure.