초록 ▼

A high efficiency aerodynamic sail system for boats comprises a triangular fabric sail pivotally suspended at its head from the apex of a tripod mast structure such that air impinging upon the luff of the sail is free from the turbulent wake of any upwind structure. The foot of the sail is attached

A high efficiency aerodynamic sail system for boats comprises a triangular fabric sail pivotally suspended at its head from the apex of a tripod mast structure such that air impinging upon the luff of the sail is free from the turbulent wake of any upwind structure. The foot of the sail is attached only at its tack and clew ends to opposite ends of a spar which is pivotally attached at its center to a short stub mast centrally positioned in respect to the tripod mast. The sail luff and leech side deflections are caused to be identical by cables to provide a constant angle of attack of the sail to the wind along the entire sail height. A sail-shaping batten having a longitudinally varying cross section is employed along the foot of the sail. Loading of the batten by pressure generated by the wind causes the batten, and thus the sail, to assume an optimum airfoil shape. The sail luff and leech are cut to the deflection shape of the luff and leech cables, respectively, to assure a substantially constant camber along the entire height of the sail. In two variations the sail head is hung from a conventional single mast. In the first variation the sail tack and the sail clew are attached to opposite ends of a boom, the tack end of which is pivotally attached to one end of a second, shorter boom, which is, at its other end, rotatably attached to the mast. The sail may be positioned aweather of the mast to create a slot effect between the sail and the mast. In the second variation the sail tack is attached to one end of a short boom and the sail clew is attached at one end of a second, longer boom. The other ends of both booms are rotatably attached to the mast.

대표청구항 ▼

A high efficiency aerodynamic sail system, comprising: a. a sail having a luff, a leech, a head and a foot, said sail having a center of area at, or below, mid-height, b. means for supporting said sail, said supporting means being adapted to suspend said sail from every corner, said supporting means

A high efficiency aerodynamic sail system, comprising: a. a sail having a luff, a leech, a head and a foot, said sail having a center of area at, or below, mid-height, b. means for supporting said sail, said supporting means being adapted to suspend said sail from every corner, said supporting means being adapted for mounting on a sailing craft, said supporting means including means to adjust the angle between said sail and said sailing craft while sailing, and to maintain said angle independently of the strength of the incident wind, c. means for causing the luff-to-leech airfoil chords of said sail to be virtually parallel each with the others when said sail is generating an aerodynamic lift force, said means for causing the luff-to-leech airfoil chords of said sail to be virtually parallel with each other when said sail is generating an aerodynamic lift force being capable of adjustment while said sail is in use, and, d. means for connecting said sail to said means for matching the leeward deflections of said luff and leech.