Patent ID: 6287077
Filing Date: 2001-09-11
Classification: B63H,F02B

Abstract:
A boat propeller comprising:a housing adapted to be fixed to a boat;a hub rotatable about a main axis on the housing;a plurality of generally radially projecting vanes pivotable on the hub;an operating core shaft coaxially received in the hub, rotatable about the main axis but axially nondisplaceable relative thereto, and having a rear end projecting axially from the hub and a front end;means including a yoke fixed to the rear core-shaft end and respective rods fixed to the yoke and connected to the vanes for pivoting the vanes on angular movement of the core shaft about the main axis;a cylinder axially fixed in the housing at the front core-shaft end;a piston axially displaceable in the cylinder;a nut element having a nonbinding internal screwthread;a screw element threaded in the nut element, one of the elements being axially coupled to the piston and the other of the elements being axially coupled to the core-shaft front end; andmeans for pressurizing the cylinder and thereby axially displacing the piston and, by axial-to-rotary conversion via the elements, rotating the core shaft.