| 摘要 |
A transducer apparatus (30) for marine pleasure craft (28) employs only gravity-induced forces to always orient its electroacoustic transducer (40) in a downward direction (42) or other predetermined direction. The apparatus mounts on the transom (32) or hull of a pleasure craft, and includes a housing (80) having a smoothly shaped exterior to permit laminar water flow past it. The housing (80, 82, 84) has a liquid filled internal cavity (86, 88) of preferably spherical shape (90) in which a transducer assembly (40, 240, 340) is mounted. The assembly includes an electroacoustic transducer (150) and a transducer support structure (152) that allows the transducer to move freely on account of gravity about a center of rotation in at least two orthogonal directions as the craft pitches and/or rolls. The transducer assembly is preferably constructed to have an overall specific gravity about equal to that of the liquid (140) in the cavity so it essentially floats in the liquid. |
