Patent ID: 7465205
Filing Date: 2008-12-16
Classification: A63B

Abstract:
1. A method for providing a hydrofoil comprising: (a) providing a predetermined body that is arranged to experience reciprocating motion; (b) providing at least one substantially flexible elongated rib member connected to said predetermined body, said rib member having a rib root portion adjacent said predetermined body and a rib free end portion remote from said rib root portion and said predetermined body, said rib member having a predetermined length between said rib root portion and said rib free end portion, said rib having a longitudinal midpoint, said rib member having a first half portion between said longitudinal midpoint and said rib root portion, said rib member having a second half portion between said midpoint and said rib free end portion; (b) connecting a blade member to said rib member, said blade member having outer side edges, opposing surfaces, a blade free end portion spaced from said predetermined body and said rib root portion, and a blade root portion between said blade free end portion and said predetermined body; (c) providing said rib member with sufficient flexibility along said predetermined length to cause a significant portion of said second half portion to experience opposite movement that occurs in the opposite direction of said first half portion during at least one inversion phase of said reciprocating motion, said rib transitioning along its length from a substantially ovular cross sectional shape at said rib root portion, to a substantially circular cross sectional shape at said rib free end portion.