Nippon Kokan Kabushiki Kaisha

Japan Marine Machinery Development Association

Kazuhiko Yoshimi

Kazuyuki Shimizu

Katsunori Kusumoto

Kazuo Nakanishi

Hideki Namura

Takashi Watari

Shoichi Sato

Shigeru Nagai

Yoichi Endo

Terukazu Doi

A rigid marine sail comprises a vertical mast secured onto a deck of a ship; at least one pivot shaft provided substantially in parallel with the mast; a left sail portion and a right sail portion pivotally secured respectively to the left side and the right side of the mast in parallel therewith through the at least one pivot shaft; and at least one drive mechanism for symmetrically pivoting the left sail portion and the right sail portion relative to the mast around the pivot shaft between a deployed position and a folded position. Each of the drive mechanisms include a set of a cylinder and a piston rod secured horizontally to the mast; a pair of L-shaped first levers, each of the first levers horizontally engaging at an end thereof with an end of the piston rod, the pair of first levers being bilaterally arranged symmetrically relative to a vertical plane which passes through the vertical axis of the mast and is parallel to the longitudinal direction of the ship, the pair of first levers being symmetrically pivotable around respective fulcrums thereof; and a pair of second levers, each of the second levers horizontally engaging at an end thereof with the other end of each of the pair of first levers, and the pair of second levers engaging at the other ends thereof respectively with the left sail portion and the right sail portion.

Rigid marine sail

A rigid marine sail has a rigid left sail portion and a rigid right sail portion, both of which are pivotally secured to a mast on a ship so as to be pivotable about one common pivot axis which extends substantially parallel to the mast of the ship. The common pivot axis is spaced ahead of the mast with respect to the direction of intended movement of the ship. The left and right sail portions are foldable to an operable position by pivoting them about the common pivot axis and are also foldable to a streamlined folded inoperable position by being pivoted about the one common pivot axis, the left and right sail portions being substantially parallel to each other and closely facing each other when they are in their streamlined folded inoperable positions. A shroud is provided ahead of the common pivot axis with respect to the direction of movement of the ship. When the left and right sail portions are in their folded inoperable position, the shroud spans a gap between them to reduce air resistance. When the sail portions are unfolded to their operable positions, only the left and right sail portions serve as sail members and they also shield the shroud from exposure to the wind.

Method for operating a rigid marine sail

Growing community of inventors

Yokohama, Japan

Kazuhiko Yoshimi