Abstract: The specification discloses a method and system for retreading tires wherein an uncured gum layer disposed between a vehicle tire carcass and a pre-cured tire tread is vulcanized by RF energy. An annular air bladder is received within the tire carcass and includes an annular conductive grounding strip. A hub is received within the center opening of the tire carcass and connects to the grounding strip. A chamber capable of withstanding high pressures is dimensioned to receive the tire carcass. A shaft is horizontally rotatably disposed in the chamber and is adapted to connect to the hub. Drive structure extends through the wall of the chamber in order to rotate the shaft at a predetermined speed. A source of pressure is provided for pressurizing the interior of the chamber. An RF antenna extends from the chamber to a position adjacent the tire tread when the tire carcass is mounted for rotation about the shaft. A source of RF energy is located outside the chamber.

Abstract: Disclosed is a truck air foil having upper and lower elongated generally rectangular panels hinged one to the other along opposed edges. A bracket on the forward face of the cargo box pivotally mounts the upper edge of the upper panel while the lower edge of the lower panel is vertically adjustably mounted whereby the angle of attack or both the upper and lower panels is adjustable. A panel, arcuate in cross section, forms a transition surface between the upper panel and the top of the cargo box to reduce air separation from the top surface of the cargo box and minimize drag. In another form, triangular panels are disposed vertically along the lower panel to divide and deflect the air stream laterally toward the opposite sides of the truck air foil likewise to minimize air separation and drag along the sides of the truck.