| 摘要 |
<p>A windsurfer has a surfboard (2) which carries a sail (5) fixed to a frame (1). The frame consists of two curved upper members (12,13) and two straight lower members (10,11). A cross-member with opposite handed screw thread at each end screw into fittings at the junctions of the curved and straight members. This cross-member enables the shape of the sail (5) to be adjusted. The frame is attached to the surfboard by a universal joint (7). The frame can be pivoted about this joint by handles (45,46) fixed to two bars (8) mounted on either side of the adjustable cross-member and free to rotate about its axis. This type of sail and its method of control enable the windsurfer to be sailed both against the wind and close to the wind.</p> |
