PROPELLER Russian patent published in 1995 - IPC

FIELD: shipbuilding. SUBSTANCE: helical surfaces of propeller blades which are of convex-concave profile are conical; apexes of cones are shifted from blade root in proportion to magnitude of solid angles. EFFECT: reduced consumption of labour required for manufacture since propeller blade surface are machined at universal lathes, vertical turning lathes, milling or grinding machines. 2 cl, 2 dwg