| 摘要 |
<p>58 . "Method and apparatus for a phased array transducer". A stacked phased array type of transducer has a single electroacoustic transducer element supported intermediately of an elongated tube having a plurality of ports and an end wall at each end thereof for transmitting and receiving acoustic waves broadside the longitudinal axis of the array tube. The element has a first vibratile surface in direct acoustical communication with the external transmission medium and a second vibratile surface in direct acoustical communication with the tube internal transmission medium. The tube is provided with at least one annular port spaced longitudinally from each end of the element for providing acoustic coupling between the internal and external transmission mediums with the tube interior providing acoustic transmission paths internally of the tube communicating between the second vibratile surface and the external transmission medium at each one of the ports. The physical spacing of the ports, the aperture area of the ports, the effective acoustical wave path length internally of the tube, and the acoustical impedance of the end walls of the tube are configured to provide predetermined phase shift and acoustic transmission characteristics of the transmission paths between the second vibratile surface of the transducer element and the external transmission medium immediately adjacent each port to provide a maximum acoustic wave pattern broadside or perpendicular to the longitudinal axis of the tube. Baffles are provided to phase shift control the acoustical wave internally of the tube. In an embodiment transducer elements and ports are alternately positioned along the tube length.</p> |
