MARINE PROPELLER Russian patent published in 2003 - IPC

FIELD: shipbuilding; marine propellers with reciprocating drives for low-speed water craft. SUBSTANCE: proposed propeller has body with drive arranged inside it for setting plates-blades in reciprocating motion. Drive is made in form of hydraulic cylinders. Central hydraulic cylinder is rigidly secured inside propeller body. Plates- blades are articulated on rod. Other hydraulic cylinders are articulated in upper and lower parts of body. Rods are articulated with respective plates-blades which create thrust in vertical position due to displacement of water from propeller body at forward stroke of all hydraulic cylinders; while changing from vertical to horizontal position, they create thrust due to displacement of water entrapped between them at reverse stroke of central hydraulic cylinder. Plates-blades are provided with side plates; at vertical position of plates-blades they form clearance with propeller body for creating thrust due to displacement of water through this clearance in changing horizontal position to vertical position at reverse stroke of upper and lower hydraulic cylinders. EFFECT: avoidance of idling; reduced resistance to motion; increased thrust; enhanced operational efficiency. 5 dwg