| 摘要 |
<p>The mast of the windsurfer has a bottom section (3) pivoted on the mast by a universal joint (4) and with a loose fit into a blind hole in the top of the board. For normal sailing the joint lies just above the surface of the board. If the sail tips and traps the foot of the user then the leverage lifts the base out of the board, with the mast retained by a safety strap (9). The safety strap prevents complete loosening of the mast while allowing the mast to lift and prevent injury. A sprung ratchet in a restricted neck hole can also be used.</p> |
