Rooftop drag reducing device for multi-truck shipment when mounted

Abstract

The rooftop drag reducing device comprises a top and a bottom and may be mounted to the cab of trucks for semi-trailers at the factory. The device may then be conveniently collapsed with the top fitting inside the bottom when multiple trucks are shipped with the second and third truck, for example, having their front wheels mounted to the fifth wheel of the truck in front of them. Since the drag reducing device has had its height reduced it will pass under low bridges. The device is initially integrally molded in one piece and cut into the top and bottom portions along a oblique cut line step. The top may be left connected to the bottom at the front to form a living hinge. Alternatively, a piano hinge may be used to connect the top and bottom portions at the front thereof. Bolts along the sides are used to hold the top in its upright position. These bolts pass through stepped side flanges which strengthen the device. The rear of the top is closed to form a rigid box-like structure to resist sway. Trim tabs may be integrally molded into the top at its rear. Each trim tab is preferably only cut out three quarters around its perimeter so that it remains mounted at the front thereof to the top by a living hinge of molded material. The device may be mounted to the roofs of truck cabs by conventional brackets or by means of bolts through an integral horizontally disposed flange around its lower periphery.