Apparatus for adjusting and locking pitch of a variable pitch propeller on a ship

Apparatus for optimizing pitch of a propeller by adjusting and substantially permanently locking the pitch of a propeller when said propeller is installed on a ship and said propeller is substantially stopped, said apparatus comprising:

• a plurality of variable pitch propeller blade assemblies rotatably mounted in a propeller blade hub, said propeller blade hub for being mounted on a propeller shaft of a ship;
• means for rotating said plurality of rotatable propeller blade assemblies in said propeller blade hub only when said propeller and its propeller shaft are substantially stopped;
• each said propeller blade assembly having a longitudinal axis, said longitudinal axis extending from said propeller hub outwardly therefrom to a tip portion of its corresponding propeller blade;
• each of said propeller blade assemblies having a conical portion disposed in said propeller blade hub;
• means for being disposed within said ship for controlling said rotating means, said controlling means for controlling said rotating means during adjustment of said pitch of said propeller blade assemblies;
• means for locking said plurality of propeller blade assemblies only when said propeller and its propeller shaft are substantially stopped in said propeller blade hub and for substantially permanently locking said blade assemblies in said hub,
• said locking means comprising:
• on each said propeller blade assembly, a ring having an inner, annular conical surface, each said propeller blade assembly having a propeller blade root with a conical portion, said conical surface of said conical ring being disposed about said conical portion of the corresponding propeller blade assembly, said conical surface of said conical ring being disposed adjacent to said conical portion of its corresponding propeller blade root, said conical portion of the corresponding propeller blade assembly having a substantially similar conical pitch as, and substantially mating with, said conical surface of its corresponding conical ring;
• each said ring having an outer, annular surface opposite said inner annular surface, said outer surface having means to be engaged with said hub, said hub having means to be engaged with said means to be engaged of said outer annular surface of each said ring;
• means for pressing into engagement and locking said inner conical surface with its corresponding conical portion of its corresponding propeller blade assembly and said means to be engaged of said outer surface of each said conical ring with its means to be engaged of said hub, whereby each of said propeller blade assemblies is firmly, non-rotatably engaged and locked in said propeller blade hub;
• said means for rotating said propeller blade assemblies comprising means for rotating said propeller blade assemblies over a portion of a blade rotation substantially less than a complete blade rotation;
• each said propeller blade having its root disposed in said propeller blade hub;
• said means for rotating said propeller blade comprising:
• a journal protruding, at a peripheral portion, from each said propeller blade root, said journal rotating with its corresponding propeller blade root about a corresponding longitudinal axis of its corresponding blade, each said journal rotating with its root at a substantially constant distance from its corresponding propeller blade longitudinal axis;
• elongated rod means connected to each said journal for rotating each said propeller blade;
• a plurality of elongated orifices in said propeller hub for receiving its corresponding elongated rod means, each said elongated rod means having a longitudinal axis;
• means for moving each said elongated rod means along its longitudinal axis and through its corresponding orifice;
• each said orifice having a given play between an inner surface thereof and an outer surface of its corresponding elongated rod means extending therethrough, thereby providing only limited play, of each said lever in each said corresponding orifice, substantially at right angles to each said longitudinal axis of each said elongated rod means whereby only a limited longitudinal movement of each said elongated rod means is provided for optimizing said propeller pitch over its range of rotation;
• and
• said means for pressing each said ring into engagement and locking comprising:
• hydraulic means for providing hydraulic oil under pressure;
• an end surface on said ring being disposed to be acted upon by said oil under pressure provided by said hydraulic means for substantially permanently locking said ring against said propeller blade assembly and said hub only when said propeller and its propeller shaft are substantially stopped.