Reversible stern drive marine propulsion system

A reversible stern drive system comprising:

• a rotatable input shaft connected to a rotatable drive unit, said input shaft having a driving member attached thereto;
• a rotatable propeller shaft;
• a first rotatable intermediate shaft located substantially parallel to said propeller shaft and said input shaft;
• a second rotatable intermediate shaft located substantially parallel to said propeller shaft, said input shaft, and said first intermediate shaft;
• a first driven member rotatable about said first intermediate shaft and coupled to said driving member to rotate said first driven member in a first rotational direction, said first driven member being selectively coupled to said first intermediate shaft;
• a second driven member rotatable about said second intermediate shaft and coupled to said first driven member so as to rotate said second driven member in a second rotational direction, said second driven member being selectively coupled to said second intermediate shaft;
• a continuous drive member looped about each of said first intermediate shaft, said second intermediate shaft, and said propeller shaft;
• wherein said continuous drive member does not impart rotation to said propeller shaft when said first driven member is not selectively coupled to said first intermediate shaft and said second driven member is not selectively coupled to said second intermediate shaft.

A reversible stern drive system comprising:

• a rotatable input shaft connected to a rotatable drive unit, said input shaft having a driving member attached thereto;
• a first rotatable propeller shaft and a second rotatable propeller shaft mounted concentrically with said first propeller shaft;
• a first rotatable intermediate shaft located substantially parallel to said first and second propeller shafts and said input shaft, said first intermediate shaft having at least two sprockets rotatably arranged thereon, of which at least one of said at least two sprockets being selectively coupled to said first intermediate shaft;
• a second rotatable intermediate shaft located substantially parallel to said first and second propeller shafts, said input shaft, and said first intermediate shaft, said second intermediate shaft having at least two sprockets rotatably arranged thereon, of which at least one of said at least two sprockets being selectively coupled to said second intermediate shaft;
• a first driven member attached to said first intermediate shaft and coupled to said driving member to rotate said first intermediate shaft in a first rotational direction;
• a second driven member attached to said second intermediate shaft and coupled to said first driven member so as to rotate said second intermediate shaft in a second rotational direction;
• a first continuous drive member looped about said first propeller shaft, at least one of said at least two sprockets rotatably arranged on said first intermediate shaft, and one of said at least two sprockets rotatably arranged on said second intermediate shaft,
• wherein said first continuous drive member rotates said first propeller shaft in a first propeller rotational direction when at least one of said at least two sprockets is selectively coupled to said first intermediate shaft;
• a second continuous drive member looped about said second propeller shaft, said other of said at least two sprockets rotatably arranged on said first intermediate shaft, and said other of said at least two sprockets rotatably arranged on said second intermediate shaft,
• wherein said second continuous drive member rotates said second propeller shaft in a second propeller rotational direction when said other of said at least two sprockets is selectively coupled to said second intermediate shaft.

A reversible stern drive system comprising:

• a rotatable input shaft connected to a rotatable drive unit, said input shaft having a driving member attached thereto;
• a first rotatable propeller shaft and a second rotatable propeller shaft mounted concentrically with said first propeller shaft;
• a first rotatable intermediate shaft located substantially parallel to said first and second propeller shafts and said input shaft, said first intermediate shaft having at least two sprockets rotatably arranged thereon, of which at least one of said at least two sprockets being selectively coupled to said first intermediate shaft;
• a second rotatable intermediate shaft located substantially parallel to said first and second propeller shafts, said input shaft, and said first intermediate shaft, said second intermediate shaft having at least two sprockets rotatably arranged thereon, of which at least one of said at least two sprockets being selectively coupled to said second intermediate shaft;
• a first driven member attached to said first intermediate shaft and coupled to said driving member to rotate said first intermediate shaft in a first rotational direction;
• a second driven member attached to said second intermediate shaft and coupled to said first driven member to rotate said second intermediate shaft in a second rotational direction;
• a first continuous drive member looped about said first propeller shaft, at least one of said at least two sprockets mounted to said first intermediate shaft, and one of said at least two sprockets mounted to said second intermediate shaft;
• a second continuous drive member looped about said second propeller shaft, said other of said at least two sprockets mounted to said first intermediate shaft, and said other of said at least two sprockets mounted to said second intermediate shaft;
• wherein said first continuous drive member does not impart rotation to said first propeller shaft when neither of said at least two sprockets mounted to said first intermediate shaft is selectively coupled to said first intermediate shaft;
• and
• wherein said second continuous drive member does not impart rotation to said second propeller shaft when neither of said at least two sprockets mounted to said second intermediate shaft is selectively coupled to said second intermediate shaft.

A marine propulsion system comprising:

• a stern drive housing;
• a gearbox;
• a driving member, a first driven member, a second driven member, a first clutch, and a second clutch disposed in said gearbox;
• an input shaft, a first intermediate shaft, a second intermediate shaft positioned in proper relation to said driving member, said first driven member, said second driven member, said first clutch, and said second clutch and disposed in said gearbox;
• a lip seal positioned between each of said first intermediate shaft, said second intermediate shaft, and said input shaft and a corresponding opening in said gearbox such that a lubricant in said gearbox is contained therein;
• wherein
• said gearbox and said driving member, said first driven member, said second driven member, said first clutch, said second clutch, said input shaft, said first intermediate shaft, and said second intermediate shaft may be unitarily removable from said stern drive housing without draining said lubricant.