Patent ID: 7503818

Claim:
A marine drive apparatus adapted for being engaged with and driven by an engine drive shaft penetrating the hull of a vessel, the apparatus comprising and mutually engaged in a sequence of: a universal joint adapted to be secured to the hull; a first screw shaft supporting a first screw; a first gear set driven by the first screw shaft; a second screw shaft driven by the first gear set; a second gear set driven by the second screw shaft; a third screw shaft driven by the second gear set and supporting a third screw; and a second screw supported by the second screw shaft at a terminal end thereof; the first and second gear sets enclosed within a water-tight enclosure; the first gear set enabling rotational speed differentiation between the first and second screw shafts; the second gear set enabling rotational sense reversal between the second and third screw shafts; the apparatus further comprising an actuator engaged with the enclosure and adapted for securement to the hull, the actuator positioned and adapted for changing an angle of attack of the first, second and third screws.